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IEEE Transactions on energy conversion |
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Ajouter le résultat dans votre panierNovel identification method of stator single phase-to-ground fault for cable-wound generators / Gao, Yan in IEEE transactions on energy conversion, Vol. 23 n°2 (Juin 2008)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 349 - 357
Titre : Novel identification method of stator single phase-to-ground fault for cable-wound generators Type de document : texte imprimé Auteurs : Gao, Yan, Auteur ; Xiangning Lin, Auteur ; Qing Tian, Auteur Année de publication : 2008 Article en page(s) : pp. 349 - 357 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Electric generators; electrical faults; fault diagnosis; stators Résumé : A new criterion to detect the stator single phase-to-ground fault for Powerformer is proposed in this paper, which is based on the direction of zero-sequence compositive power flow. By virtue of the analysis of new fault characteristics of Powerformer and the comparison with conventional methods, a novel identification scheme is put forward. The proposed approach detects the ground fault by analyzing the power direction. Only zero-sequence current from the terminal of Powerformer and zero-sequence voltage from the busbar are used in this scheme. Combined with third-harmonic principle, it can provide a 100% coverage of fault detection for the stator windings of Powerformer. The effectiveness of this scheme is validated with the Matlab simulation results. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505389&sortType%3Das [...] [article] Novel identification method of stator single phase-to-ground fault for cable-wound generators [texte imprimé] / Gao, Yan, Auteur ; Xiangning Lin, Auteur ; Qing Tian, Auteur . - 2008 . - pp. 349 - 357.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 349 - 357
Mots-clés : Electric generators; electrical faults; fault diagnosis; stators Résumé : A new criterion to detect the stator single phase-to-ground fault for Powerformer is proposed in this paper, which is based on the direction of zero-sequence compositive power flow. By virtue of the analysis of new fault characteristics of Powerformer and the comparison with conventional methods, a novel identification scheme is put forward. The proposed approach detects the ground fault by analyzing the power direction. Only zero-sequence current from the terminal of Powerformer and zero-sequence voltage from the busbar are used in this scheme. Combined with third-harmonic principle, it can provide a 100% coverage of fault detection for the stator windings of Powerformer. The effectiveness of this scheme is validated with the Matlab simulation results. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505389&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 358 - 362
Titre : Influence of design parameters on linear induction motor end effect Type de document : texte imprimé Auteurs : Creppe, R.C., Auteur ; Covolan Ulson, J.A., Auteur ; Rodrigues, J.F., Auteur Année de publication : 2008 Article en page(s) : pp. 358 - 362 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Linear induction motors; mathematical analysis Résumé : In this paper, a factor referred to as kf for linear induction motor end effect analysis is presented. The mathematical model takes into account the longitudinal entry end effect. The entry end effect produces considerable distortion in magnetic field distribution. It is shown how this influence is derived from the machine-developed force that is calculated through the application of the 1-D theory. The kf factor establishes the relationship between the longitudinal end effect and machine parameters, mainly the number of magnetic poles, secondary resistivity, and frequency. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4489613&sortType%3Das [...] [article] Influence of design parameters on linear induction motor end effect [texte imprimé] / Creppe, R.C., Auteur ; Covolan Ulson, J.A., Auteur ; Rodrigues, J.F., Auteur . - 2008 . - pp. 358 - 362.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 358 - 362
Mots-clés : Linear induction motors; mathematical analysis Résumé : In this paper, a factor referred to as kf for linear induction motor end effect analysis is presented. The mathematical model takes into account the longitudinal entry end effect. The entry end effect produces considerable distortion in magnetic field distribution. It is shown how this influence is derived from the machine-developed force that is calculated through the application of the 1-D theory. The kf factor establishes the relationship between the longitudinal end effect and machine parameters, mainly the number of magnetic poles, secondary resistivity, and frequency. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4489613&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 363 - 371
Titre : Windings temperature and loss of life of an induction machine under voltage unbalance combined with over- or undervoltages Type de document : texte imprimé Auteurs : Gnacinski, P., Auteur Année de publication : 2008 Article en page(s) : pp. 363 - 371 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous machines; machine windings; overvoltage Résumé : This paper deals with the effect of simultaneous voltage unbalance and over- or undervoltage on windings temperature and thermal loss of life of an induction cage machine. The presented results of investigations are based on the experiment and thermal modeling. The influence of an angle of the complex voltage unbalance factor (CVUF) on machine heating is considered. The effect of synergy of voltage unbalance and voltage rms value deviation is presented. Two induction machines of different properties are compared. One of them has a comparatively weakly saturated magnetic circuit, and the other a comparatively strongly saturated circuit. The former is especially exposed to overheating in the conditions of undervoltage, and the latter in the conditions of overvoltage. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4476161&sortType%3Das [...] [article] Windings temperature and loss of life of an induction machine under voltage unbalance combined with over- or undervoltages [texte imprimé] / Gnacinski, P., Auteur . - 2008 . - pp. 363 - 371.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 363 - 371
Mots-clés : Asynchronous machines; machine windings; overvoltage Résumé : This paper deals with the effect of simultaneous voltage unbalance and over- or undervoltage on windings temperature and thermal loss of life of an induction cage machine. The presented results of investigations are based on the experiment and thermal modeling. The influence of an angle of the complex voltage unbalance factor (CVUF) on machine heating is considered. The effect of synergy of voltage unbalance and voltage rms value deviation is presented. Two induction machines of different properties are compared. One of them has a comparatively weakly saturated magnetic circuit, and the other a comparatively strongly saturated circuit. The former is especially exposed to overheating in the conditions of undervoltage, and the latter in the conditions of overvoltage. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4476161&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 372 - 381
Titre : Capacitors required for maximum power of a self-excited single-phase induction generator using a three-phase machine Type de document : texte imprimé Auteurs : Mahato, S.N., Auteur ; S. P. Singh, Auteur ; Sharma, M.P., Auteur Année de publication : 2008 Article en page(s) : pp. 372 - 381 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous generators; power capacitors; power factor Résumé : This paper aims to determine the optimal capacitors required for maximum output power of a single-phase self-excited induction generator (SEIG), using a three-phase machine feeding inductive as well as capacitive loads. The generator consists of a three-phase star-connected induction machine with three capacitors and a single-phase load. The algorithm, which gives directly the values of the optimal capacitors for the maximum power output and the maximum power available, has been developed using the steady-state model of the SEIG and sequential unconstrained minimization technique (SUMT). The variations of the maximum power output with power factor (pf) of loads (both inductive and capacitive) and speed of the SEIG have been presented. The voltage regulation of the generator is small due to the effect of the two series capacitors. Experimental results have shown the effectiveness and accuracy of the developed algorithm. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457822&sortType%3Das [...] [article] Capacitors required for maximum power of a self-excited single-phase induction generator using a three-phase machine [texte imprimé] / Mahato, S.N., Auteur ; S. P. Singh, Auteur ; Sharma, M.P., Auteur . - 2008 . - pp. 372 - 381.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 372 - 381
Mots-clés : Asynchronous generators; power capacitors; power factor Résumé : This paper aims to determine the optimal capacitors required for maximum output power of a single-phase self-excited induction generator (SEIG), using a three-phase machine feeding inductive as well as capacitive loads. The generator consists of a three-phase star-connected induction machine with three capacitors and a single-phase load. The algorithm, which gives directly the values of the optimal capacitors for the maximum power output and the maximum power available, has been developed using the steady-state model of the SEIG and sequential unconstrained minimization technique (SUMT). The variations of the maximum power output with power factor (pf) of loads (both inductive and capacitive) and speed of the SEIG have been presented. The voltage regulation of the generator is small due to the effect of the two series capacitors. Experimental results have shown the effectiveness and accuracy of the developed algorithm. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457822&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 382 - 392
Titre : Modeling of induction machines using a voltage-behind-reactance formulation Type de document : texte imprimé Auteurs : Liwei, Wang, Auteur ; Jatskevich, J., Auteur ; Pekarek, S.D., Auteur Année de publication : 2008 Article en page(s) : pp. 382 - 392 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous machines; power convertors; power electronics Résumé : Over the past several years, there has been renewed interest in modeling electrical machines using phase (abc) variables. This paper considers modeling induction machines using phase variables in a voltage-behind-reactance (VBR) formulation. Specifically, three VBR models are proposed wherein the rotor electrical subsystem is modeled using flux linkages as state variables expressed in the qd reference frame. The stator electrical dynamics are represented in abc phase coordinates that enable direct interface of the machine model to an external network. Such a direct interface is advantageous when the machine is fed from a power electronic converter and/or when the modeling is carried out using circuit-based simulators. Computer studies of an induction machine demonstrate that the proposed VBR models achieve a 740% improvement in computational efficiency as compared with the traditional coupled-circuit phase-domain model. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505399&sortType%3Das [...] [article] Modeling of induction machines using a voltage-behind-reactance formulation [texte imprimé] / Liwei, Wang, Auteur ; Jatskevich, J., Auteur ; Pekarek, S.D., Auteur . - 2008 . - pp. 382 - 392.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 382 - 392
Mots-clés : Asynchronous machines; power convertors; power electronics Résumé : Over the past several years, there has been renewed interest in modeling electrical machines using phase (abc) variables. This paper considers modeling induction machines using phase variables in a voltage-behind-reactance (VBR) formulation. Specifically, three VBR models are proposed wherein the rotor electrical subsystem is modeled using flux linkages as state variables expressed in the qd reference frame. The stator electrical dynamics are represented in abc phase coordinates that enable direct interface of the machine model to an external network. Such a direct interface is advantageous when the machine is fed from a power electronic converter and/or when the modeling is carried out using circuit-based simulators. Computer studies of an induction machine demonstrate that the proposed VBR models achieve a 740% improvement in computational efficiency as compared with the traditional coupled-circuit phase-domain model. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505399&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 393 - 402
Titre : Combined flux observer with signal injection enhancement for wide speed range sensorless direct torque control of IPMSM drives Type de document : texte imprimé Auteurs : Andreescu, G., Auteur ; Pitic, C.I., Auteur ; Blaabjerg, F., Auteur Année de publication : 2008 Article en page(s) : pp. 393 - 402 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Permanent magnet motors; rotors; synchronous motor drives; torque control Résumé : This paper proposes a motion-sensorless control system using direct torque control with space vector modulation for interior permanent magnet synchronous motor (IPMSM) drives, for wide speed range operation, including standstill. A novel stator flux observer with variable structure uses a combined voltage-current model with PI compensator for low-speed operations. As speed increases, the observer switches gradually to a PI compensated closed-loop voltage model, which is solely used at high speeds. High-frequency rotating-voltage injection with a single D-module bandpass vector filter and a phase-locked loop state observer with a new synchronization procedure are used to estimate the rotor position, which is needed only by the current model in stator flux observer at low speeds. A new rotor speed estimator for the whole speed-loop range, based on the stator flux speed estimation with a new dynamic correction depending on estimated torque, is proposed and tested. Extensive simulation results and significant experimental results provided good performance for the proposed IPMSM sensorless system in more than 1:1000 speed range, under full-load operation, from very low speeds (1 r/min experimental) up to rated speed. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456515&sortType%3Das [...] [article] Combined flux observer with signal injection enhancement for wide speed range sensorless direct torque control of IPMSM drives [texte imprimé] / Andreescu, G., Auteur ; Pitic, C.I., Auteur ; Blaabjerg, F., Auteur . - 2008 . - pp. 393 - 402.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 393 - 402
Mots-clés : Permanent magnet motors; rotors; synchronous motor drives; torque control Résumé : This paper proposes a motion-sensorless control system using direct torque control with space vector modulation for interior permanent magnet synchronous motor (IPMSM) drives, for wide speed range operation, including standstill. A novel stator flux observer with variable structure uses a combined voltage-current model with PI compensator for low-speed operations. As speed increases, the observer switches gradually to a PI compensated closed-loop voltage model, which is solely used at high speeds. High-frequency rotating-voltage injection with a single D-module bandpass vector filter and a phase-locked loop state observer with a new synchronization procedure are used to estimate the rotor position, which is needed only by the current model in stator flux observer at low speeds. A new rotor speed estimator for the whole speed-loop range, based on the stator flux speed estimation with a new dynamic correction depending on estimated torque, is proposed and tested. Extensive simulation results and significant experimental results provided good performance for the proposed IPMSM sensorless system in more than 1:1000 speed range, under full-load operation, from very low speeds (1 r/min experimental) up to rated speed. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456515&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 403 - 411
Titre : A 40-pulse AC--DC converter fed vector-controlled induction motor drive Type de document : texte imprimé Auteurs : Singh, B., Auteur ; Gairola, S., Auteur Année de publication : 2008 Article en page(s) : pp. 403 - 411 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : AC-DC power convertors; autotransformers; harmonic distortion; induction motor drives; machine vector control; rectifying circuits Résumé : In this paper, a novel autotransformer for a 40-pulse ac-dc converter configuration is designed, modeled, simulated, and implemented to feed vector-controlled induction motor drive (VCIMD). The proposed converter consists of two paralleled ten-pulse ac-dc converters along with pulse doubling circuit at dc bus. Each ten-pulse ac-dc converter involves five-phase diode bridge rectifiers. It improves power quality at ac mains, and it meets IEEE-519 standard requirements at varying loads. A set of power quality indexes on input ac mains and dc bus for a VCIMD fed from 20-pulse and 6-pulse converters is also given to compare their performance. It is observed that input current total harmonic distortion (THD) of much less than 5% is possible with the proposed topology at varying loads. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4459268&sortType%3Das [...] [article] A 40-pulse AC--DC converter fed vector-controlled induction motor drive [texte imprimé] / Singh, B., Auteur ; Gairola, S., Auteur . - 2008 . - pp. 403 - 411.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 403 - 411
Mots-clés : AC-DC power convertors; autotransformers; harmonic distortion; induction motor drives; machine vector control; rectifying circuits Résumé : In this paper, a novel autotransformer for a 40-pulse ac-dc converter configuration is designed, modeled, simulated, and implemented to feed vector-controlled induction motor drive (VCIMD). The proposed converter consists of two paralleled ten-pulse ac-dc converters along with pulse doubling circuit at dc bus. Each ten-pulse ac-dc converter involves five-phase diode bridge rectifiers. It improves power quality at ac mains, and it meets IEEE-519 standard requirements at varying loads. A set of power quality indexes on input ac mains and dc bus for a VCIMD fed from 20-pulse and 6-pulse converters is also given to compare their performance. It is observed that input current total harmonic distortion (THD) of much less than 5% is possible with the proposed topology at varying loads. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4459268&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 412 - 422
Titre : Robust adaptive control of linear induction motors with unknown end-effect and secondary resistance Type de document : texte imprimé Auteurs : Kuang-Yow Lian, Auteur ; Cheng-Yao Hung, Auteur ; Chian-Song Chiu, Auteur Année de publication : 2008 Article en page(s) : pp. 412 - 422 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Adaptive control; control system synthesis; linear induction motors; machine control; position control; robust control; velocity control Résumé : This paper proposes a novel robust adaptive speed/ position tracking control for a linear induction motor (LIM) with both end-effect and secondary resistance unknown. The practical current-fed controlled LIM, with residual current error, is considered, i.e., the traditional ideal current-loop assumption is relaxed. More practical conditions, such as bounded primary voltage and a finite absolute-integral of current tracking error is considered. To overcome the high nonlinearity and nonzero current error, a backstepping method, combining virtual desired variable synthesis, is developed for the speed and position tracking. Then, the controller achieves asymptotic speed and position tracking even with unknown parameters and immeasurable secondary flux. Furthermore, the effect of the residual current error is attenuated in an L2 -gain sense. The experiments for several scenarios are carried out to verify the theoretical result. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4374092&sortType%3Das [...] [article] Robust adaptive control of linear induction motors with unknown end-effect and secondary resistance [texte imprimé] / Kuang-Yow Lian, Auteur ; Cheng-Yao Hung, Auteur ; Chian-Song Chiu, Auteur . - 2008 . - pp. 412 - 422.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 412 - 422
Mots-clés : Adaptive control; control system synthesis; linear induction motors; machine control; position control; robust control; velocity control Résumé : This paper proposes a novel robust adaptive speed/ position tracking control for a linear induction motor (LIM) with both end-effect and secondary resistance unknown. The practical current-fed controlled LIM, with residual current error, is considered, i.e., the traditional ideal current-loop assumption is relaxed. More practical conditions, such as bounded primary voltage and a finite absolute-integral of current tracking error is considered. To overcome the high nonlinearity and nonzero current error, a backstepping method, combining virtual desired variable synthesis, is developed for the speed and position tracking. Then, the controller achieves asymptotic speed and position tracking even with unknown parameters and immeasurable secondary flux. Furthermore, the effect of the residual current error is attenuated in an L2 -gain sense. The experiments for several scenarios are carried out to verify the theoretical result. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4374092&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 423 - 432
Titre : Average-value modeling of brushless DC motors with 120° voltage source inverter Type de document : texte imprimé Auteurs : Qiang, Han, Auteur ; Samoylenko, N., Auteur ; Jatskevich, J., Auteur Année de publication : 2008 Article en page(s) : pp. 423 - 432 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Brushless DC motors; commutation; invertors; nonlinear equations; permanent magnet machines; stators; switching convertors; synchronous machines Résumé : This paper describes average-value modeling of brushless dc (BLDC) motor-inverter systems, which is challenging due to the complicated switching patterns of the stator currents. A new average-value model (AVM) that appropriately includes commutation and conduction subintervals of the BLDC motor with a 120deg inverter is presented. The proposed model is explicit and uses a proper qd model of the permanent magnet synchronous machine. The required commutation angle is represented as a nonlinear algebraic function, which is readily obtained from the detailed simulation. The studies conducted are based on two typical industrial motors with different electrical time constants, and include hardware measurements, detailed simulation, and comparison with a previously published AVM. The proposed model is shown to be more accurate in terms of both large and small-signal analysis and is applicable to both types of motors. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505390&sortType%3Das [...] [article] Average-value modeling of brushless DC motors with 120° voltage source inverter [texte imprimé] / Qiang, Han, Auteur ; Samoylenko, N., Auteur ; Jatskevich, J., Auteur . - 2008 . - pp. 423 - 432.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 423 - 432
Mots-clés : Brushless DC motors; commutation; invertors; nonlinear equations; permanent magnet machines; stators; switching convertors; synchronous machines Résumé : This paper describes average-value modeling of brushless dc (BLDC) motor-inverter systems, which is challenging due to the complicated switching patterns of the stator currents. A new average-value model (AVM) that appropriately includes commutation and conduction subintervals of the BLDC motor with a 120deg inverter is presented. The proposed model is explicit and uses a proper qd model of the permanent magnet synchronous machine. The required commutation angle is represented as a nonlinear algebraic function, which is readily obtained from the detailed simulation. The studies conducted are based on two typical industrial motors with different electrical time constants, and include hardware measurements, detailed simulation, and comparison with a previously published AVM. The proposed model is shown to be more accurate in terms of both large and small-signal analysis and is applicable to both types of motors. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505390&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 433 - 443
Titre : Analytical determination of DC-bus utilization limits in multiphase VSI supplied AC drives Type de document : texte imprimé Auteurs : Levi, E., Auteur ; Dujic, D., Auteur ; Jones, M., Auteur Année de publication : 2008 Article en page(s) : pp. 433 - 443 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : AC motor drives; PWM invertors Résumé : Two-level multiphase voltage source inverters (VSIs) are typically used as the supply for multiphase machines. Such machines are often with concentrated winding in which case, certain low-order stator current harmonics are injected to provide torque enhancement. Also, a multimotor drive system can be realized by connecting a number of multiphase machines in series, using phase transposition while supplying the whole system from a single multiphase VSI. In both situations, it is important to know the limits of the inverter operation in the linear modulation region. This paper develops a simple method that enables analytical determination of the boundaries of the linear modulation region for all multiphase inverters with a prime number of phases. The limits are independent of the actual pulse width modulation (PWM) method utilized, and are equally applicable to both carrier-based and space vector PWM techniques. Theoretical considerations are verified experimentally using the five-phase and seven-phase VSI rigs. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505394&sortType%3Das [...] [article] Analytical determination of DC-bus utilization limits in multiphase VSI supplied AC drives [texte imprimé] / Levi, E., Auteur ; Dujic, D., Auteur ; Jones, M., Auteur . - 2008 . - pp. 433 - 443.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 433 - 443
Mots-clés : AC motor drives; PWM invertors Résumé : Two-level multiphase voltage source inverters (VSIs) are typically used as the supply for multiphase machines. Such machines are often with concentrated winding in which case, certain low-order stator current harmonics are injected to provide torque enhancement. Also, a multimotor drive system can be realized by connecting a number of multiphase machines in series, using phase transposition while supplying the whole system from a single multiphase VSI. In both situations, it is important to know the limits of the inverter operation in the linear modulation region. This paper develops a simple method that enables analytical determination of the boundaries of the linear modulation region for all multiphase inverters with a prime number of phases. The limits are independent of the actual pulse width modulation (PWM) method utilized, and are equally applicable to both carrier-based and space vector PWM techniques. Theoretical considerations are verified experimentally using the five-phase and seven-phase VSI rigs. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505394&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 444 - 459
Titre : Asynchronous machine rotor fault diagnosis technique using complex wavelets Type de document : texte imprimé Auteurs : Tsoumas, I. P., Auteur ; Georgoulas, G., Auteur ; Mitronikas, E. D., Auteur Année de publication : 2008 Article en page(s) : pp. 444 - 459 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous machines; fault diagnosis; feature extraction; rotors; spectral analysis; support vector machines; wavelet transforms Résumé : This paper introduces a novel approach for the detection of rotor faults in asynchronous machines, based on wavelet analysis of the stator phase current. To be more specific, the measured stator phase current is filtered through a complex wavelet. Theoretical analysis validates that the spectrum of the modulus of the result of the filtering is free from the fundamental supply frequency component, and the fault characteristics can be highlighted. This is advantageous, especially if the induction machine operates at low slip values, where the characteristic frequency components of the rotor fault are very close to the fundamental frequency component. At the same time, by matching the wavelet function to the frequencies of the faulty components, a narrow bandpass filter at the frequency region of the fault characteristic spectral components is obtained. Furthermore, in the context of this paper, features extracted using the proposed technique are used as input to a support vector machine classifier that is employed for the detection of the rotor fault. Simulation and experimental results demonstrate the effectiveness of the proposed technique. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4378206&sortType%3Das [...] [article] Asynchronous machine rotor fault diagnosis technique using complex wavelets [texte imprimé] / Tsoumas, I. P., Auteur ; Georgoulas, G., Auteur ; Mitronikas, E. D., Auteur . - 2008 . - pp. 444 - 459.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 444 - 459
Mots-clés : Asynchronous machines; fault diagnosis; feature extraction; rotors; spectral analysis; support vector machines; wavelet transforms Résumé : This paper introduces a novel approach for the detection of rotor faults in asynchronous machines, based on wavelet analysis of the stator phase current. To be more specific, the measured stator phase current is filtered through a complex wavelet. Theoretical analysis validates that the spectrum of the modulus of the result of the filtering is free from the fundamental supply frequency component, and the fault characteristics can be highlighted. This is advantageous, especially if the induction machine operates at low slip values, where the characteristic frequency components of the rotor fault are very close to the fundamental frequency component. At the same time, by matching the wavelet function to the frequencies of the faulty components, a narrow bandpass filter at the frequency region of the fault characteristic spectral components is obtained. Furthermore, in the context of this paper, features extracted using the proposed technique are used as input to a support vector machine classifier that is employed for the detection of the rotor fault. Simulation and experimental results demonstrate the effectiveness of the proposed technique. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4378206&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 460 - 465
Titre : Experimental verification of critical-speed increase of single-phase induction machines via winding reconfiguration with solid-state switches Type de document : texte imprimé Auteurs : Schraud, J., Auteur ; Fuchs, E. F., Auteur ; Fuchs, H. A., Auteur Année de publication : 2008 Article en page(s) : pp. 460 - 465 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Induction motors; machine windings; power electronics; starting; switching; switching circuits Résumé : The concept of online electronic switching of windings will be applied to a single-phase induction motor with two separate windings with different pole numbers p1 = 4 and p2 = 6 and an auxiliary winding required for starting. During switchover from the low-speed winding to the high-speed winding, and vice versa, lasting less than a few milliseconds, small electrical torque and speed transients occur. Relying on closed-loop speed control, a smooth speed response is measured. This concept is, therefore, applicable to variable-speed drives, where a large speed range is desirable. Test data indicate that a speed-control range from 600 to 4000 r/min is obtainable with a single-phase induction motor. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505397&sortType%3Das [...] [article] Experimental verification of critical-speed increase of single-phase induction machines via winding reconfiguration with solid-state switches [texte imprimé] / Schraud, J., Auteur ; Fuchs, E. F., Auteur ; Fuchs, H. A., Auteur . - 2008 . - pp. 460 - 465.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 460 - 465
Mots-clés : Induction motors; machine windings; power electronics; starting; switching; switching circuits Résumé : The concept of online electronic switching of windings will be applied to a single-phase induction motor with two separate windings with different pole numbers p1 = 4 and p2 = 6 and an auxiliary winding required for starting. During switchover from the low-speed winding to the high-speed winding, and vice versa, lasting less than a few milliseconds, small electrical torque and speed transients occur. Relying on closed-loop speed control, a smooth speed response is measured. This concept is, therefore, applicable to variable-speed drives, where a large speed range is desirable. Test data indicate that a speed-control range from 600 to 4000 r/min is obtainable with a single-phase induction motor. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505397&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 466 - 473
Titre : Torque harmonic compensation in a synchronous reluctance motor Type de document : texte imprimé Auteurs : Bianchi, N., Auteur ; Bolognani, S., Auteur ; Bon, D., Auteur Année de publication : 2008 Article en page(s) : pp. 466 - 473 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Harmonics suppression; reluctance motors; torque Résumé : The torque behavior of a synchronous reluctance motor [including the permanent magnet (PM) assisted configuration] is deeply analyzed. An analytical model is developed, showing the dependence of the torque ripple on the rotor geometry. The results of this model allow to individuate the position of the flux--barrier ends so as to minimize the torque ripple. In addition, the proposed strategy to minimize the ripple is not only based on a suitable choice of the flux--barrier ends, but this choice is combined with the adoption of a rotor formed by two different laminations. This strategy allows an optimal compensation of the torque harmonics so that a smooth torque is achieved. Some motor prototypes have been manufactured and tested in a suitable testing bench. The torque versus position characteristics have been measured at very low speed, to avoid a reduction of the high-order torque harmonics. The experimental results confirm the effectiveness of the proposed strategy. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457820&sortType%3Das [...] [article] Torque harmonic compensation in a synchronous reluctance motor [texte imprimé] / Bianchi, N., Auteur ; Bolognani, S., Auteur ; Bon, D., Auteur . - 2008 . - pp. 466 - 473.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 466 - 473
Mots-clés : Harmonics suppression; reluctance motors; torque Résumé : The torque behavior of a synchronous reluctance motor [including the permanent magnet (PM) assisted configuration] is deeply analyzed. An analytical model is developed, showing the dependence of the torque ripple on the rotor geometry. The results of this model allow to individuate the position of the flux--barrier ends so as to minimize the torque ripple. In addition, the proposed strategy to minimize the ripple is not only based on a suitable choice of the flux--barrier ends, but this choice is combined with the adoption of a rotor formed by two different laminations. This strategy allows an optimal compensation of the torque harmonics so that a smooth torque is achieved. Some motor prototypes have been manufactured and tested in a suitable testing bench. The torque versus position characteristics have been measured at very low speed, to avoid a reduction of the high-order torque harmonics. The experimental results confirm the effectiveness of the proposed strategy. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457820&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 474 - 483
Titre : Evaluation of the degradation of generator stator ground wall insulation under multistresses aging Type de document : texte imprimé Auteurs : Zhidong, Jia, Auteur ; Xiang, Peng, Auteur ; Zhicheng, Guan, Auteur Année de publication : 2008 Article en page(s) : pp. 474 - 483 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Weibull distribution; ageing; electric breakdown; electric generators; machine insulation Résumé : The actual stator bars of an 18 kV/300 MW generator were used for accelerated multistress aging tests to investigate the degradation of ground insulation. An aging system with combined stresses including thermal, electrical, mechanical vibration, and thermomechanical factors was used to test the aging of stator bar specimens. The nondestructive parameters including partial discharge (PD) quantities and dissipation factor parameters were measured during aging test in order to evaluate the degradation of stator ground wall insulation. At the end of the aging test, an AC breakdown test was performed on the bars in order to obtain the remaining breakdown voltage (BDV) after their nondestructive data had been measured. The changes of nondestructive parameters indicated that the degradation of ground wall insulation. For example, the changes of skewness of indicated the shape of voids in ground insulation changes from flat to narrow, and even exhibits treeing, which is dangerous to insulation because it shortens the effective distance of insulation between high voltage and the ground. The results obtained are summarized as follows. The BDV data fit a Weibull distribution. The correlation between the dissipation factor, the PD parameters, and the breakdown voltage were analyzed, among which the skewness of the average discharge had the most correlation with breakdown voltage. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505392&sortType%3Das [...] [article] Evaluation of the degradation of generator stator ground wall insulation under multistresses aging [texte imprimé] / Zhidong, Jia, Auteur ; Xiang, Peng, Auteur ; Zhicheng, Guan, Auteur . - 2008 . - pp. 474 - 483.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 474 - 483
Mots-clés : Weibull distribution; ageing; electric breakdown; electric generators; machine insulation Résumé : The actual stator bars of an 18 kV/300 MW generator were used for accelerated multistress aging tests to investigate the degradation of ground insulation. An aging system with combined stresses including thermal, electrical, mechanical vibration, and thermomechanical factors was used to test the aging of stator bar specimens. The nondestructive parameters including partial discharge (PD) quantities and dissipation factor parameters were measured during aging test in order to evaluate the degradation of stator ground wall insulation. At the end of the aging test, an AC breakdown test was performed on the bars in order to obtain the remaining breakdown voltage (BDV) after their nondestructive data had been measured. The changes of nondestructive parameters indicated that the degradation of ground wall insulation. For example, the changes of skewness of indicated the shape of voids in ground insulation changes from flat to narrow, and even exhibits treeing, which is dangerous to insulation because it shortens the effective distance of insulation between high voltage and the ground. The results obtained are summarized as follows. The BDV data fit a Weibull distribution. The correlation between the dissipation factor, the PD parameters, and the breakdown voltage were analyzed, among which the skewness of the average discharge had the most correlation with breakdown voltage. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505392&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 484 - 491
Titre : Analysis and detection of short circuits in fractional horsepower commutator machines Type de document : texte imprimé Auteurs : Retana, R., Auteur ; Paweletz, A., Auteur ; Herzog, H., Auteur Année de publication : 2008 Article en page(s) : pp. 484 - 491 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Commutator motors; fault diagnosis; harmonics; short-circuit currents Résumé : An improved mathematical model for transient simulations of commutator machines is presented in this paper. This model can simulate and predict the line current harmonics during healthy and faulty operation conditions. A lumped parameter model that considers every single coil in the stator and rotor as a separate electrical and magnetic circuit is proposed. Self and mutual inductances of the coils are estimated by means of the winding function approach (WFA), accounting for the most relevant space harmonics in the machine air gap. The commutation is modeled by using the real brush width and assuming that the brush-commutator contact resistance is a function uniquely of their contact area, which depends on the armature position. Short circuits between adjacent commutator bars are investigated. It is shown that the model achieves good accuracy, reproducing fairly well the armature current ripple for healthy and faulty operation of the machine. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4476138&sortType%3Das [...] [article] Analysis and detection of short circuits in fractional horsepower commutator machines [texte imprimé] / Retana, R., Auteur ; Paweletz, A., Auteur ; Herzog, H., Auteur . - 2008 . - pp. 484 - 491.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 484 - 491
Mots-clés : Commutator motors; fault diagnosis; harmonics; short-circuit currents Résumé : An improved mathematical model for transient simulations of commutator machines is presented in this paper. This model can simulate and predict the line current harmonics during healthy and faulty operation conditions. A lumped parameter model that considers every single coil in the stator and rotor as a separate electrical and magnetic circuit is proposed. Self and mutual inductances of the coils are estimated by means of the winding function approach (WFA), accounting for the most relevant space harmonics in the machine air gap. The commutation is modeled by using the real brush width and assuming that the brush-commutator contact resistance is a function uniquely of their contact area, which depends on the armature position. Short circuits between adjacent commutator bars are investigated. It is shown that the model achieves good accuracy, reproducing fairly well the armature current ripple for healthy and faulty operation of the machine. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4476138&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 492 - 498
Titre : Steady-state analysis of a dual-winding reluctance generator with a multiple-barrier rotor Type de document : texte imprimé Auteurs : Fukami, T., Auteur ; Momiyama, M., Auteur ; Khatibisepehr Shima, Auteur Année de publication : 2008 Article en page(s) : pp. 492 - 498 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Magnetic leakage; reluctance generators Résumé : This paper presents the modeling and steady-state performance of a novel dual-winding reluctance generator (DWRG) that uses a multiple-barrier (MB) rotor. A simple mathematical model was developed, and the effects of external parameters (speed, field current, and load) on the steady-state performance were analyzed. Experimental results conducted on a prototype machine were also provided to justify the theoretical approach and performance calculations. The developed model takes into account the magnetic saturation and core loss and enables a quantitative prediction of load characteristics from the no-load test data. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4475788&sortType%3Das [...] [article] Steady-state analysis of a dual-winding reluctance generator with a multiple-barrier rotor [texte imprimé] / Fukami, T., Auteur ; Momiyama, M., Auteur ; Khatibisepehr Shima, Auteur . - 2008 . - pp. 492 - 498.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 492 - 498
Mots-clés : Magnetic leakage; reluctance generators Résumé : This paper presents the modeling and steady-state performance of a novel dual-winding reluctance generator (DWRG) that uses a multiple-barrier (MB) rotor. A simple mathematical model was developed, and the effects of external parameters (speed, field current, and load) on the steady-state performance were analyzed. Experimental results conducted on a prototype machine were also provided to justify the theoretical approach and performance calculations. The developed model takes into account the magnetic saturation and core loss and enables a quantitative prediction of load characteristics from the no-load test data. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4475788&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 499 - 508
Titre : A voltage-behind-reactance synchronous machine model with saturation and arbitrary rotor network representation Type de document : texte imprimé Auteurs : Aliprantis, D. C., Auteur ; Wasynczuk, O., Auteur ; Rodriguez Valdez, C.D., Auteur Année de publication : 2008 Article en page(s) : pp. 499 - 508 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Synchronous machines; transfer functions Résumé : A voltage-behind-reactance formulation of a synchronous machine model is set forth, which incorporates saturation and cross-saturation, and is general enough to encapsulate a variety of rotor structures by use of arbitrary linear networks instead of equivalent circuits. Specifically, the model's equations - originally expressed in the qd-axes framework - are rewritten in such a way as to allow the actual abc stator windings to be represented by inductive branches, which can then be naturally connected in the desired circuit topology, e.g., to a rectifier. The model's predictions are validated against experimental results. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4509482&sortType%3Das [...] [article] A voltage-behind-reactance synchronous machine model with saturation and arbitrary rotor network representation [texte imprimé] / Aliprantis, D. C., Auteur ; Wasynczuk, O., Auteur ; Rodriguez Valdez, C.D., Auteur . - 2008 . - pp. 499 - 508.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 499 - 508
Mots-clés : Synchronous machines; transfer functions Résumé : A voltage-behind-reactance formulation of a synchronous machine model is set forth, which incorporates saturation and cross-saturation, and is general enough to encapsulate a variety of rotor structures by use of arbitrary linear networks instead of equivalent circuits. Specifically, the model's equations - originally expressed in the qd-axes framework - are rewritten in such a way as to allow the actual abc stator windings to be represented by inductive branches, which can then be naturally connected in the desired circuit topology, e.g., to a rectifier. The model's predictions are validated against experimental results. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4509482&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 509 - 518
Titre : Voltage and frequency controller for a three-phase four-wire autonomous wind energy conversion system Type de document : texte imprimé Auteurs : Singh, B., Auteur ; Kasal, G. K., Auteur Année de publication : 2008 Article en page(s) : pp. 509 - 518 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : PWM power convertors; asynchronous generators; frequency control; harmonics suppression; voltage regulators; wind power Résumé : This paper deals with control of voltage and frequency of an autonomous wind energy conversion system (AWECS) based on capacitor-excited asynchronous generator and feeding three-phase four-wire loads. The proposed controller consists of three single-phase insulated gate bipolar junction transistor (IGBT)-based voltage source converters (VSCs) and a battery at dc link. These three single-phase VSCs are connected to each phase of the generator through three single-phase transformers. The proposed controller is having bidirectional flow capability of active and reactive powers by which it controls the system voltage and frequency with variation of consumer loads and the speed of the wind. VSCs along with transformer function as a voltage regulator, a harmonic eliminator, a load balancer, and a neutral current compensator while the battery is used to control the active power flow which, in turn, maintains the constant system frequency. The complete electromechanical system is modeled and simulated in the MATLAB using the Simulink and the power system blockset (PSB) toolboxes. The simulated results are presented to demonstrate the capability of the proposed controller as a voltage and frequency regulator, harmonic eliminator, load balancer, and neutral current compensator for different electrical (varying consumer loads) and mechanical (varying wind speed) dynamic conditions in an autonomous wind energy conversion system. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505398&sortType%3Das [...] [article] Voltage and frequency controller for a three-phase four-wire autonomous wind energy conversion system [texte imprimé] / Singh, B., Auteur ; Kasal, G. K., Auteur . - 2008 . - pp. 509 - 518.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 509 - 518
Mots-clés : PWM power convertors; asynchronous generators; frequency control; harmonics suppression; voltage regulators; wind power Résumé : This paper deals with control of voltage and frequency of an autonomous wind energy conversion system (AWECS) based on capacitor-excited asynchronous generator and feeding three-phase four-wire loads. The proposed controller consists of three single-phase insulated gate bipolar junction transistor (IGBT)-based voltage source converters (VSCs) and a battery at dc link. These three single-phase VSCs are connected to each phase of the generator through three single-phase transformers. The proposed controller is having bidirectional flow capability of active and reactive powers by which it controls the system voltage and frequency with variation of consumer loads and the speed of the wind. VSCs along with transformer function as a voltage regulator, a harmonic eliminator, a load balancer, and a neutral current compensator while the battery is used to control the active power flow which, in turn, maintains the constant system frequency. The complete electromechanical system is modeled and simulated in the MATLAB using the Simulink and the power system blockset (PSB) toolboxes. The simulated results are presented to demonstrate the capability of the proposed controller as a voltage and frequency regulator, harmonic eliminator, load balancer, and neutral current compensator for different electrical (varying consumer loads) and mechanical (varying wind speed) dynamic conditions in an autonomous wind energy conversion system. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505398&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 519 - 528
Titre : Influence of tower shadow and wind turbulence on the performance of power system stabilizers for DFIG-based wind farms Type de document : texte imprimé Auteurs : Hughes, F.M., Auteur ; Anaya-Lara, O., Auteur ; Ramtharan, G., Auteur Année de publication : 2008 Article en page(s) : pp. 519 - 528 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Aerodynamics; asynchronous generators; poles and towers; power system simulation; power system stability; turbulence; wind power plants Résumé : The aim of the paper is to demonstrate the way in which mechanical power variations, due to tower shadow and wind turbulence, influence control performance of power system stabilizer (PSS) loops for doubly-fed induction generators (DFIGs). The PSS auxiliary loops are applied on a specific DFIG control scheme, the flux magnitude and angle controller (FMAC). However, since the PSS signal is applied at the output of the basic controller, the PSS performance characteristics displayed are deemed typical for DFIG control schemes in general. The relative capabilities of PSS controllers based on stator power, rotor speed, and network frequency, when the DFIG turbine is subjected to aerodynamic torque variations, are investigated via simulation studies. A two-generator aggregate model of a wind farm is introduced, which enables the influence of tower shadow and wind turbulence on both an individual turbine and on the overall wind farm itself to be assessed. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4488039&sortType%3Das [...] [article] Influence of tower shadow and wind turbulence on the performance of power system stabilizers for DFIG-based wind farms [texte imprimé] / Hughes, F.M., Auteur ; Anaya-Lara, O., Auteur ; Ramtharan, G., Auteur . - 2008 . - pp. 519 - 528.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 519 - 528
Mots-clés : Aerodynamics; asynchronous generators; poles and towers; power system simulation; power system stability; turbulence; wind power plants Résumé : The aim of the paper is to demonstrate the way in which mechanical power variations, due to tower shadow and wind turbulence, influence control performance of power system stabilizer (PSS) loops for doubly-fed induction generators (DFIGs). The PSS auxiliary loops are applied on a specific DFIG control scheme, the flux magnitude and angle controller (FMAC). However, since the PSS signal is applied at the output of the basic controller, the PSS performance characteristics displayed are deemed typical for DFIG control schemes in general. The relative capabilities of PSS controllers based on stator power, rotor speed, and network frequency, when the DFIG turbine is subjected to aerodynamic torque variations, are investigated via simulation studies. A two-generator aggregate model of a wind farm is introduced, which enables the influence of tower shadow and wind turbulence on both an individual turbine and on the overall wind farm itself to be assessed. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4488039&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 529 - 534
Titre : Analysis of the cost per kilowatt hour to store electricity Type de document : texte imprimé Auteurs : Poonpun, P., Auteur ; Jewell, W.T., Auteur Année de publication : 2008 Article en page(s) : pp. 529 - 534 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Energy storage; life cycle costing; power grids; power system economics Résumé : This paper presents a cost analysis of grid-connected electric energy storage. Various energy storage technologies are considered in the analysis. Life-cycle cost analysis is used. The results are presented in terms of the cost added to electricity stored and discharged, in US dollar per kilowatt hour. Results are compared with wholesale and retail electricity costs and with the cost of conventional pumped hydro storage. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456517&sortType%3Das [...] [article] Analysis of the cost per kilowatt hour to store electricity [texte imprimé] / Poonpun, P., Auteur ; Jewell, W.T., Auteur . - 2008 . - pp. 529 - 534.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 529 - 534
Mots-clés : Energy storage; life cycle costing; power grids; power system economics Résumé : This paper presents a cost analysis of grid-connected electric energy storage. Various energy storage technologies are considered in the analysis. Life-cycle cost analysis is used. The results are presented in terms of the cost added to electricity stored and discharged, in US dollar per kilowatt hour. Results are compared with wholesale and retail electricity costs and with the cost of conventional pumped hydro storage. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456517&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 535 - 543
Titre : Control of variable speed wind turbines in islanded mode of operation Type de document : texte imprimé Auteurs : Kanellos, F. D., Auteur ; Hatziargyriou, N. D., Auteur Année de publication : 2008 Article en page(s) : pp. 535 - 543 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Distributed power generation; power generation control; wind turbines Résumé : Nowadays, technology evolution and deregulation of the electric utility industry enable distributed generation (DG) to play an increasing role in locally satisfying the expanding power demand. In this paper, the islanded operation of an electrical grid supplied by wind turbines, which belong to the most rapidly expanding DG technologies, is studied. Control strategies for power electronics interface of variable speed wind turbines, ensuring fast control of frequency and voltage, are proposed. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505393&sortType%3Das [...] [article] Control of variable speed wind turbines in islanded mode of operation [texte imprimé] / Kanellos, F. D., Auteur ; Hatziargyriou, N. D., Auteur . - 2008 . - pp. 535 - 543.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 535 - 543
Mots-clés : Distributed power generation; power generation control; wind turbines Résumé : Nowadays, technology evolution and deregulation of the electric utility industry enable distributed generation (DG) to play an increasing role in locally satisfying the expanding power demand. In this paper, the islanded operation of an electrical grid supplied by wind turbines, which belong to the most rapidly expanding DG technologies, is studied. Control strategies for power electronics interface of variable speed wind turbines, ensuring fast control of frequency and voltage, are proposed. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505393&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 544 - 550
Titre : Noniterative method to approximate the effective load carrying capability of a wind plant Type de document : texte imprimé Auteurs : D'Annunzio, C., Auteur ; Santoso, S., Auteur Année de publication : 2008 Article en page(s) : pp. 544 - 550 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Approximation theory; reliability; wind power plants Résumé : The effective load carrying capability (ELCC) is considered the preferred metric to evaluate the capacity value of added wind generation. However, the classical method of computing this metric requires substantial reliability modeling and an iterative process that is quite computationally intensive. Consequently, a noniterative method of estimating a wind plant's ELCC is proposed in this paper. Inspired by Garver's approximation and derived based on well-known reliability concepts, the proposed method provides an excellent approximation while requiring only minimal reliability modeling and no computationally-intensive iterative process. It computes ELCC estimates from a single function using only the wind plant's multistate probabilistic representation and a graphically determined parameter that characterizes the existing power system. After presenting the complete mathematical derivation of this function, the method is applied to compute the ELCC estimates of various wind plants at different penetration levels. It is shown that the resultant ELCC estimates only slightly overestimate the classically computed values by relative errors of 2.5% or less. Furthermore, the proposed method yields more accurate ELCC estimates than the capacity factor approximation, which is commonly used to approximate the ELCC of a wind plant. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4481561&sortType%3Das [...] [article] Noniterative method to approximate the effective load carrying capability of a wind plant [texte imprimé] / D'Annunzio, C., Auteur ; Santoso, S., Auteur . - 2008 . - pp. 544 - 550.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 544 - 550
Mots-clés : Approximation theory; reliability; wind power plants Résumé : The effective load carrying capability (ELCC) is considered the preferred metric to evaluate the capacity value of added wind generation. However, the classical method of computing this metric requires substantial reliability modeling and an iterative process that is quite computationally intensive. Consequently, a noniterative method of estimating a wind plant's ELCC is proposed in this paper. Inspired by Garver's approximation and derived based on well-known reliability concepts, the proposed method provides an excellent approximation while requiring only minimal reliability modeling and no computationally-intensive iterative process. It computes ELCC estimates from a single function using only the wind plant's multistate probabilistic representation and a graphically determined parameter that characterizes the existing power system. After presenting the complete mathematical derivation of this function, the method is applied to compute the ELCC estimates of various wind plants at different penetration levels. It is shown that the resultant ELCC estimates only slightly overestimate the classically computed values by relative errors of 2.5% or less. Furthermore, the proposed method yields more accurate ELCC estimates than the capacity factor approximation, which is commonly used to approximate the ELCC of a wind plant. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4481561&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 551 - 558
Titre : Sliding mode power control of variable-speed wind energy conversion systems Type de document : texte imprimé Auteurs : Beltran, B., Auteur ; Ahmed-Ali, T., Auteur ; Benbouzid, M. E. H., Auteur Année de publication : 2008 Article en page(s) : pp. 551 - 558 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Feedback; power control; variable structure systems; wind power Résumé : This paper addresses the problem of controlling power generation in variable-speed wind energy conversion systems (VS-WECS). These systems have two operation regions depending on the wind turbine tip-speed ratio. They are distinguished by minimum phase behavior in one of these regions and a nonminimum phase in the other one. A sliding mode control strategy is then proposed to ensure stability in both operation regions and to impose the ideal feedback control solution despite model uncertainties. The proposed sliding mode control strategy presents attractive features such as robustness to parametric uncertainties of the turbine and the generator as well as to electric grid disturbances. The proposed sliding mode control approach has been simulated on a 1.5-MW three-blade wind turbine to evaluate its consistency and performance. The next step was the validation using the National Renewable Energy Laboratory (NREL) wind turbine simulator called the fatigue, aerodynamics, structures, and turbulence code (FAST). Both simulation and validation results show that the proposed control strategy is effective in terms of power regulation. Moreover, the sliding mode approach is arranged so as to produce no chattering in the generated torque that could lead to increased mechanical stress because of strong torque variations. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458228&sortType%3Das [...] [article] Sliding mode power control of variable-speed wind energy conversion systems [texte imprimé] / Beltran, B., Auteur ; Ahmed-Ali, T., Auteur ; Benbouzid, M. E. H., Auteur . - 2008 . - pp. 551 - 558.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 551 - 558
Mots-clés : Feedback; power control; variable structure systems; wind power Résumé : This paper addresses the problem of controlling power generation in variable-speed wind energy conversion systems (VS-WECS). These systems have two operation regions depending on the wind turbine tip-speed ratio. They are distinguished by minimum phase behavior in one of these regions and a nonminimum phase in the other one. A sliding mode control strategy is then proposed to ensure stability in both operation regions and to impose the ideal feedback control solution despite model uncertainties. The proposed sliding mode control strategy presents attractive features such as robustness to parametric uncertainties of the turbine and the generator as well as to electric grid disturbances. The proposed sliding mode control approach has been simulated on a 1.5-MW three-blade wind turbine to evaluate its consistency and performance. The next step was the validation using the National Renewable Energy Laboratory (NREL) wind turbine simulator called the fatigue, aerodynamics, structures, and turbulence code (FAST). Both simulation and validation results show that the proposed control strategy is effective in terms of power regulation. Moreover, the sliding mode approach is arranged so as to produce no chattering in the generated torque that could lead to increased mechanical stress because of strong torque variations. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458228&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 559 - 569
Titre : Designing an adaptive fuzzy controller for maximum wind energy extraction Type de document : texte imprimé Auteurs : Galdi, V., Auteur ; Piccolo, A., Auteur ; Siano, P., Auteur Année de publication : 2008 Article en page(s) : pp. 559 - 569 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Adaptive control; control engineering computing; fuzzy control; genetic algorithms; least squares approximations; power system control; wind turbines Résumé : The wind power production spreading, also aided by the transition from constant to variable speed operation, involves the development of efficient control systems to improve the effectiveness of power production systems. This paper presents a data-driven design methodology able to generate a Takagi-Sugeno-Kang (TSK) fuzzy model for maximum energy extraction from variable speed wind turbines. In order to obtain the TSK model, fuzzy clustering methods for partitioning the input-output space, combined with genetic algorithms, and recursive least-squares optimization methods for model parameter adaptation are used. The implemented TSK fuzzy model, as confirmed by some simulation results on a doubly fed induction generator connected to a power system, exhibits high speed of computation, low memory occupancy, fault tolerance, and learning capability. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458230&sortType%3Das [...] [article] Designing an adaptive fuzzy controller for maximum wind energy extraction [texte imprimé] / Galdi, V., Auteur ; Piccolo, A., Auteur ; Siano, P., Auteur . - 2008 . - pp. 559 - 569.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 559 - 569
Mots-clés : Adaptive control; control engineering computing; fuzzy control; genetic algorithms; least squares approximations; power system control; wind turbines Résumé : The wind power production spreading, also aided by the transition from constant to variable speed operation, involves the development of efficient control systems to improve the effectiveness of power production systems. This paper presents a data-driven design methodology able to generate a Takagi-Sugeno-Kang (TSK) fuzzy model for maximum energy extraction from variable speed wind turbines. In order to obtain the TSK model, fuzzy clustering methods for partitioning the input-output space, combined with genetic algorithms, and recursive least-squares optimization methods for model parameter adaptation are used. The implemented TSK fuzzy model, as confirmed by some simulation results on a doubly fed induction generator connected to a power system, exhibits high speed of computation, low memory occupancy, fault tolerance, and learning capability. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458230&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 570 - 580
Titre : Two-level VSC-based predictive direct power control of the doubly fed induction machine with reduced power ripple at low constant switching frequency Type de document : texte imprimé Auteurs : Abad, G., Auteur ; Rodriguez, M.A., Auteur ; Poza, J., Auteur Année de publication : 2008 Article en page(s) : pp. 570 - 580 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous machines; machine vector control; power control; predictive control; transient response; voltage control Résumé : In this paper, a new predictive direct power control (DPC) technique is presented for the doubly fed induction machine (DFIM). Based on this predictive control, the strategy is able to operate at considerably low constant switching frequencies and allows it to perform a power ripple minimization technique, in order to improve the steady-state and transient response behaviors of the machine. In addition to the control technique definition, this paper includes a conceptual analysis of DPC. On the other hand, to validate the control strategy, it will be experimentally compared to the well-known voltage frequency control, the vector control, and the nonpredictive DPC strategy. The comparison will be carried out in terms of the steady-state behavior and transient response capacity, and it will be shown that the proposed predictive DPC technique allows to obtain the combination of the quick dynamic response of direct control techniques, and the benefits of constant switching-frequency-based control techniques. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457819&sortType%3Das [...] [article] Two-level VSC-based predictive direct power control of the doubly fed induction machine with reduced power ripple at low constant switching frequency [texte imprimé] / Abad, G., Auteur ; Rodriguez, M.A., Auteur ; Poza, J., Auteur . - 2008 . - pp. 570 - 580.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 570 - 580
Mots-clés : Asynchronous machines; machine vector control; power control; predictive control; transient response; voltage control Résumé : In this paper, a new predictive direct power control (DPC) technique is presented for the doubly fed induction machine (DFIM). Based on this predictive control, the strategy is able to operate at considerably low constant switching frequencies and allows it to perform a power ripple minimization technique, in order to improve the steady-state and transient response behaviors of the machine. In addition to the control technique definition, this paper includes a conceptual analysis of DPC. On the other hand, to validate the control strategy, it will be experimentally compared to the well-known voltage frequency control, the vector control, and the nonpredictive DPC strategy. The comparison will be carried out in terms of the steady-state behavior and transient response capacity, and it will be shown that the proposed predictive DPC technique allows to obtain the combination of the quick dynamic response of direct control techniques, and the benefits of constant switching-frequency-based control techniques. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457819&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 581 - 591
Titre : PEM fuel cells modeling and analysis through current and voltage transient behaviors Type de document : texte imprimé Auteurs : Adzakpa, K. P., Auteur ; Agbossou, K., Auteur ; Dube, Y., Auteur Année de publication : 2008 Article en page(s) : pp. 581 - 591 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Proton exchange membrane fuel cells; transients Résumé : In the last 15 years, polymer electrolyte membrane (PEM) fuel cells have received much attention, mostly through experimental and empirical studies in scientific and industrial research. In most of the works, attention has been given to the steady state analysis of the PEM fuel cells. However, considerable efforts still need to be done to explain different transient behaviors of PEM fuel cells. This paper presents an analysis of the double layer charging effect and reactant diffusion through the cathode gas diffusion layer on voltage transients after sudden current variations. These transient phenomena have typical time durations of less than 5 s. The double layer charging dynamic explains the main voltage transient behaviors when the cathode inlet pressure is constant. In this case, a bicriteria optimization procedure is proposed for numerical characterization of the double-layer charging capacitance. When the air pressure is variable, a pseudo 2-D modeling of oxygen diffusion through the cathode gas diffusion layers, based on the Stephan-Maxwell multicomponent diffusion equations, is used to explain its contribution to the voltage transient overshoots/undershoots. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458227&sortType%3Das [...] [article] PEM fuel cells modeling and analysis through current and voltage transient behaviors [texte imprimé] / Adzakpa, K. P., Auteur ; Agbossou, K., Auteur ; Dube, Y., Auteur . - 2008 . - pp. 581 - 591.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 581 - 591
Mots-clés : Proton exchange membrane fuel cells; transients Résumé : In the last 15 years, polymer electrolyte membrane (PEM) fuel cells have received much attention, mostly through experimental and empirical studies in scientific and industrial research. In most of the works, attention has been given to the steady state analysis of the PEM fuel cells. However, considerable efforts still need to be done to explain different transient behaviors of PEM fuel cells. This paper presents an analysis of the double layer charging effect and reactant diffusion through the cathode gas diffusion layer on voltage transients after sudden current variations. These transient phenomena have typical time durations of less than 5 s. The double layer charging dynamic explains the main voltage transient behaviors when the cathode inlet pressure is constant. In this case, a bicriteria optimization procedure is proposed for numerical characterization of the double-layer charging capacitance. When the air pressure is variable, a pseudo 2-D modeling of oxygen diffusion through the cathode gas diffusion layers, based on the Stephan-Maxwell multicomponent diffusion equations, is used to explain its contribution to the voltage transient overshoots/undershoots. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458227&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 592 - 602
Titre : A study on generator capacity for wind turbines under various tower heights and rated wind speeds using weibull distribution Type de document : texte imprimé Auteurs : Tai-Her Yeh, Auteur ; Wang, Li, Auteur Année de publication : 2008 Article en page(s) : pp. 592 - 602 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Weibull distribution; wind power; wind turbines Résumé : This paper presents a novel approach based on Weibull distribution to determine the capacity of wind turbine generators (WTGs) using capacity factor (CF), normalized average power (PN), and the product of CF and PN under different values of tower height and rated wind speed. Five locations for installation of WTG in Taiwan are practically examined. The proposed Weibull distribution is employed to represent probability distribution of wind speed variation, while the important relationships among mean wind speed (MWS), standard deviation of wind speed, and both scale and shape parameters of the Weibull distribution are also derived. The cost of energy (COE) and capital costs of WTG under different tower heights and various locations are also determined. It can be concluded from the simulation results of five installation locations of WTG in Taiwan that suitable values for both shape parameter and scale parameters of Weibull distribution as well as wind turbine capacity are identically important for selecting locations of installing WTG. The scale parameter of Weibull distribution also significantly affects COE, and it is important to determine whether a wind farm is good or not. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4488041&sortType%3Das [...] [article] A study on generator capacity for wind turbines under various tower heights and rated wind speeds using weibull distribution [texte imprimé] / Tai-Her Yeh, Auteur ; Wang, Li, Auteur . - 2008 . - pp. 592 - 602.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 592 - 602
Mots-clés : Weibull distribution; wind power; wind turbines Résumé : This paper presents a novel approach based on Weibull distribution to determine the capacity of wind turbine generators (WTGs) using capacity factor (CF), normalized average power (PN), and the product of CF and PN under different values of tower height and rated wind speed. Five locations for installation of WTG in Taiwan are practically examined. The proposed Weibull distribution is employed to represent probability distribution of wind speed variation, while the important relationships among mean wind speed (MWS), standard deviation of wind speed, and both scale and shape parameters of the Weibull distribution are also derived. The cost of energy (COE) and capital costs of WTG under different tower heights and various locations are also determined. It can be concluded from the simulation results of five installation locations of WTG in Taiwan that suitable values for both shape parameter and scale parameters of Weibull distribution as well as wind turbine capacity are identically important for selecting locations of installing WTG. The scale parameter of Weibull distribution also significantly affects COE, and it is important to determine whether a wind farm is good or not. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4488041&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 603 - 611
Titre : An economic dispatch model incorporating wind power Type de document : texte imprimé Auteurs : Hetzer, J., Auteur ; Yu, D.C., Auteur ; Bhattarai, K., Auteur Année de publication : 2008 Article en page(s) : pp. 603 - 611 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Power generation dispatch; power generation economics; wind power Résumé : In solving the electrical power systems economic dispatch (ED) problem, the goal is to find the optimal allocation of output power among the various generators available to serve the system load. With the continuing search for alternatives to conventional energy sources, it is necessary to include wind energy conversion system (WECS) generators in the ED problem. This paper develops a model to include the WECS in the ED problem, and in addition to the classic economic dispatch factors, factors to account for both overestimation and underestimation of available wind power are included. With the stochastic wind speed characterization based on the Weibull probability density function, the optimization problem is numerically solved for a scenario involving two conventional and two wind-powered generators. Optimal solutions are presented for various values of the input parameters, and these solutions demonstrate that the allocation of system generation capacity may be influenced by multipliers related to the risk of overestimation and to the cost of underestimation of available wind power. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505391&sortType%3Das [...] [article] An economic dispatch model incorporating wind power [texte imprimé] / Hetzer, J., Auteur ; Yu, D.C., Auteur ; Bhattarai, K., Auteur . - 2008 . - pp. 603 - 611.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 603 - 611
Mots-clés : Power generation dispatch; power generation economics; wind power Résumé : In solving the electrical power systems economic dispatch (ED) problem, the goal is to find the optimal allocation of output power among the various generators available to serve the system load. With the continuing search for alternatives to conventional energy sources, it is necessary to include wind energy conversion system (WECS) generators in the ED problem. This paper develops a model to include the WECS in the ED problem, and in addition to the classic economic dispatch factors, factors to account for both overestimation and underestimation of available wind power are included. With the stochastic wind speed characterization based on the Weibull probability density function, the optimization problem is numerically solved for a scenario involving two conventional and two wind-powered generators. Optimal solutions are presented for various values of the input parameters, and these solutions demonstrate that the allocation of system generation capacity may be influenced by multipliers related to the risk of overestimation and to the cost of underestimation of available wind power. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505391&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 612 - 621
Titre : Reactive power response of wind generators under an incremental network-loss allocation approach Type de document : texte imprimé Auteurs : De Oliveira-De Jesus, P.M., Auteur ; Castronuovo, E. D., Auteur ; Ponce de Leao, M.T., Auteur Année de publication : 2008 Article en page(s) : pp. 612 - 621 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Reactive power; wind power; wind power plants Résumé : The reactive power capability of wind generation (WG) producers can be used to provide volt/voltampere reactive (var) support in electrical distribution systems. In practice, the distribution network operator (DNO) is not able to dispatch reactive power of all generators, and such units are referred to as nondispatchable generators. Then, the reactive power of these nondispatchable generators is not a defined value, and it should accomplish the limits settled by national grid codes. This paper addresses the optimal reactive power provision of nondispatchable WG units under a loss allocation strategy based on incremental generation use of the system (GUoS) tariffs. The optimization problem is set from generators' viewpoint aiming to find the reactive power provision that minimizes the loss charges subject to operational constraints. Optimal solutions are compared with the DNOs mandatory dispatches using a reactive optimal power flow tool. Two test systems are analyzed: a 10-kV 28 bus and 60-kV 55-bus system throughout 672 and 168 h, respectively. The proposal permits to identify which units can be dispatched by the DNO due to its effect on the network. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4470326&sortType%3Das [...] [article] Reactive power response of wind generators under an incremental network-loss allocation approach [texte imprimé] / De Oliveira-De Jesus, P.M., Auteur ; Castronuovo, E. D., Auteur ; Ponce de Leao, M.T., Auteur . - 2008 . - pp. 612 - 621.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 612 - 621
Mots-clés : Reactive power; wind power; wind power plants Résumé : The reactive power capability of wind generation (WG) producers can be used to provide volt/voltampere reactive (var) support in electrical distribution systems. In practice, the distribution network operator (DNO) is not able to dispatch reactive power of all generators, and such units are referred to as nondispatchable generators. Then, the reactive power of these nondispatchable generators is not a defined value, and it should accomplish the limits settled by national grid codes. This paper addresses the optimal reactive power provision of nondispatchable WG units under a loss allocation strategy based on incremental generation use of the system (GUoS) tariffs. The optimization problem is set from generators' viewpoint aiming to find the reactive power provision that minimizes the loss charges subject to operational constraints. Optimal solutions are compared with the DNOs mandatory dispatches using a reactive optimal power flow tool. Two test systems are analyzed: a 10-kV 28 bus and 60-kV 55-bus system throughout 672 and 168 h, respectively. The proposal permits to identify which units can be dispatched by the DNO due to its effect on the network. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4470326&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 622 - 631
Titre : An integrated hybrid power supply for distributed generation applications fed by nonconventional energy sources Type de document : texte imprimé Auteurs : Jain, S., Auteur ; Agarwal, V., Auteur Année de publication : 2008 Article en page(s) : pp. 622 - 631 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : DC-DC power convertors; distributed power generation; fuel cell power plants; hybrid power systems; photovoltaic power systems Résumé : A new, hybrid integrated topology, fed by photovoltaic (PV) and fuel cell (FC) sources and suitable for distributed generation applications, is proposed. It works as an uninterruptible power source that is able to feed a certain minimum amount of power into the grid under all conditions. PV is used as the primary source of power operating near maximum power point (MPP), with the FC section (block), acting as a current source, feeding only the deficit power. The unique "integrated" approach obviates the need for dedicated communication between the two sources for coordination and eliminates the use of a separate, conventional dc/dc boost converter stage required for PV power processing, resulting in a reduction of the number of devices, components, and sensors. Presence of the FC source in parallel (with the PV source) improves the quality of power fed into the grid by minimizing the voltage dips in the PV output. Another desirable feature is that even a small amount of PV power (e.g., during low insolation), can be fed into the grid. On the other hand, excess power is diverted for auxiliary functions like electrolysis, resulting in an optimal use of the energy sources. The other advantages of the proposed system include low cost, compact structure, and high reliability, which render the system suitable for modular assemblies and "plug-n-play" type applications. All the analytical, simulation, and experimental results of this research are presented. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4488040&sortType%3Das [...] [article] An integrated hybrid power supply for distributed generation applications fed by nonconventional energy sources [texte imprimé] / Jain, S., Auteur ; Agarwal, V., Auteur . - 2008 . - pp. 622 - 631.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 622 - 631
Mots-clés : DC-DC power convertors; distributed power generation; fuel cell power plants; hybrid power systems; photovoltaic power systems Résumé : A new, hybrid integrated topology, fed by photovoltaic (PV) and fuel cell (FC) sources and suitable for distributed generation applications, is proposed. It works as an uninterruptible power source that is able to feed a certain minimum amount of power into the grid under all conditions. PV is used as the primary source of power operating near maximum power point (MPP), with the FC section (block), acting as a current source, feeding only the deficit power. The unique "integrated" approach obviates the need for dedicated communication between the two sources for coordination and eliminates the use of a separate, conventional dc/dc boost converter stage required for PV power processing, resulting in a reduction of the number of devices, components, and sensors. Presence of the FC source in parallel (with the PV source) improves the quality of power fed into the grid by minimizing the voltage dips in the PV output. Another desirable feature is that even a small amount of PV power (e.g., during low insolation), can be fed into the grid. On the other hand, excess power is diverted for auxiliary functions like electrolysis, resulting in an optimal use of the energy sources. The other advantages of the proposed system include low cost, compact structure, and high reliability, which render the system suitable for modular assemblies and "plug-n-play" type applications. All the analytical, simulation, and experimental results of this research are presented. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4488040&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 632 - 641
Titre : Voltage and frequency control of a stand alone brushless wind electric generation using generalized impedance controller Type de document : texte imprimé Auteurs : Venkatesa Perumal, B., Auteur ; Chatterjee, J. K., Auteur Année de publication : 2008 Article en page(s) : pp. 632 - 641 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : PWM invertors; asynchronous generators; brushless machines; feedback; frequency control; voltage control; wind power plants Résumé : In this paper, a new strategy for the control of terminal voltage and frequency of a stand-alone self-excited induction generator-(SEIG) based wind generator, working with variable speed and load is proposed. With a generalized impedance controller (GIC) (voltage source pulsewidth-modulated inverter with a dc-link battery), a new strategy to maintain the active and reactive power balance at the SEIG terminals has been introduced to control its terminal voltage and frequency. In the proposed control strategy, only a voltage feedback loop has been used to control both the SEIG terminal voltage and the frequency. A mathematical model of the SEIG-GIC system under wind generator environment has been developed and simulated in the MATLAB/Simulink. The simulation results are validated with the experimental ones conducted on a laboratory prototype of the SEIG-GIC system. The novelty of the present technique is that the GIC is capable of maintaining a constant SEIG terminal voltage and frequency, following both speed and load perturbations, with only a single (voltage) feedback loop. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4459443&sortType%3Das [...] [article] Voltage and frequency control of a stand alone brushless wind electric generation using generalized impedance controller [texte imprimé] / Venkatesa Perumal, B., Auteur ; Chatterjee, J. K., Auteur . - 2008 . - pp. 632 - 641.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 632 - 641
Mots-clés : PWM invertors; asynchronous generators; brushless machines; feedback; frequency control; voltage control; wind power plants Résumé : In this paper, a new strategy for the control of terminal voltage and frequency of a stand-alone self-excited induction generator-(SEIG) based wind generator, working with variable speed and load is proposed. With a generalized impedance controller (GIC) (voltage source pulsewidth-modulated inverter with a dc-link battery), a new strategy to maintain the active and reactive power balance at the SEIG terminals has been introduced to control its terminal voltage and frequency. In the proposed control strategy, only a voltage feedback loop has been used to control both the SEIG terminal voltage and the frequency. A mathematical model of the SEIG-GIC system under wind generator environment has been developed and simulated in the MATLAB/Simulink. The simulation results are validated with the experimental ones conducted on a laboratory prototype of the SEIG-GIC system. The novelty of the present technique is that the GIC is capable of maintaining a constant SEIG terminal voltage and frequency, following both speed and load perturbations, with only a single (voltage) feedback loop. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4459443&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 642 - 650
Titre : Integrated doubly fed electric alternator/active filter (IDEA), a viable power quality solution, for wind energy conversion systems Type de document : texte imprimé Auteurs : Abolhassani, M.T., Auteur ; Enjeti, P., Auteur ; Hamid Toliyat, Auteur Année de publication : 2008 Article en page(s) : pp. 642 - 650 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Active filters; alternators; power factor correction; power supply quality; reactive power control; wind power Résumé : In response to electric energy crisis and power quality concerns, a simple and low-cost variable speed integrated doubly fed electric alternator/active filter (IDEA) for wind energy conversion systems is proposed. The proposed IDEA is capable of simultaneously capturing maximum power of wind energy with fluctuating wind speed and improving power quality, which are achieved by canceling the most significant and troublesome harmonics of the utility grid. Power factor correction and reactive power control are the other two significant features of the proposed technology. The back-to-back current-regulated power converters are employed to excite the rotor of IDEA. The control strategy of rotor side power converter is based on position sensorless field oriented control method with higher power density. A laboratory prototype has been fabricated and tested, and a TMS3202407 DSP-based controller has been used to control the back-to-back power converters. Analysis and experimental results are presented to demonstrate the effectiveness of the proposed integrated IDEA. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456348&sortType%3Das [...] [article] Integrated doubly fed electric alternator/active filter (IDEA), a viable power quality solution, for wind energy conversion systems [texte imprimé] / Abolhassani, M.T., Auteur ; Enjeti, P., Auteur ; Hamid Toliyat, Auteur . - 2008 . - pp. 642 - 650.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 642 - 650
Mots-clés : Active filters; alternators; power factor correction; power supply quality; reactive power control; wind power Résumé : In response to electric energy crisis and power quality concerns, a simple and low-cost variable speed integrated doubly fed electric alternator/active filter (IDEA) for wind energy conversion systems is proposed. The proposed IDEA is capable of simultaneously capturing maximum power of wind energy with fluctuating wind speed and improving power quality, which are achieved by canceling the most significant and troublesome harmonics of the utility grid. Power factor correction and reactive power control are the other two significant features of the proposed technology. The back-to-back current-regulated power converters are employed to excite the rotor of IDEA. The control strategy of rotor side power converter is based on position sensorless field oriented control method with higher power density. A laboratory prototype has been fabricated and tested, and a TMS3202407 DSP-based controller has been used to control the back-to-back power converters. Analysis and experimental results are presented to demonstrate the effectiveness of the proposed integrated IDEA. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456348&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 651 - 658
Titre : Clustering-based performance optimization of the boiler–turbine system Type de document : texte imprimé Auteurs : Kusiak, A., Auteur ; Zhe, Song, Auteur Année de publication : 2008 Article en page(s) : pp. 651 - 658 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Boilers; data mining; power engineering computing; turbines Résumé : In this paper, two optimization models for improvement of the boiler-turbine system performance are formulated. The models are constructed using a data-mining approach. Historical process data is clustered and the discovered patterns are selected for performance improvement of the boiler-turbine system. The first model optimizes a widely used performance index, the unit heat rate. The second model minimizes the total fuel consumption while meeting the electricity demand. The strengths and weaknesses of the two models are discussed. An industrial case study illustrates the concepts presented in the paper. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456516&sortType%3Das [...] [article] Clustering-based performance optimization of the boiler–turbine system [texte imprimé] / Kusiak, A., Auteur ; Zhe, Song, Auteur . - 2008 . - pp. 651 - 658.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 651 - 658
Mots-clés : Boilers; data mining; power engineering computing; turbines Résumé : In this paper, two optimization models for improvement of the boiler-turbine system performance are formulated. The models are constructed using a data-mining approach. Historical process data is clustered and the discovered patterns are selected for performance improvement of the boiler-turbine system. The first model optimizes a widely used performance index, the unit heat rate. The second model minimizes the total fuel consumption while meeting the electricity demand. The strengths and weaknesses of the two models are discussed. An industrial case study illustrates the concepts presented in the paper. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4456516&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 659 - 668
Titre : Observer and data-driven-model-based fault detection in power plant coal mills Type de document : texte imprimé Auteurs : Odgaard, P.F., Auteur ; Bao, Lin, Auteur ; Jorgensen, S.B., Auteur Année de publication : 2008 Article en page(s) : pp. 659 - 668 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Fault location; least mean squares methods; power plants; principal component analysis Résumé : This paper presents and compares model-based and data-driven fault detection approaches for coal mill systems. The first approach detects faults with an optimal unknown input observer developed from a simplified energy balance model. Due to the time-consuming effort in developing a first principles model with motor power as the controlled variable, data-driven methods for fault detection are also investigated. Regression models that represent normal operating conditions (NOCs) are developed with both static and dynamic principal component analysis and partial least squares methods. The residual between process measurement and the NOC model prediction is used for fault detection. A hybrid approach, where a data-driven model is employed to derive an optimal unknown input observer, is also implemented. The three methods are evaluated with case studies on coal mill data, which includes a fault caused by a blocked inlet pipe. All three approaches detect the fault as it emerges. The optimal unknown input observer approach is most robust, in that, it has no false positives. On the other hand, the data-driven approaches are more straightforward to implement, since they just require the selection of appropriate confidence limit to avoid false detection. The proposed hybrid approach is promising for systems where a first principles model is cumbersome to obtain. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4470327&sortType%3Das [...] [article] Observer and data-driven-model-based fault detection in power plant coal mills [texte imprimé] / Odgaard, P.F., Auteur ; Bao, Lin, Auteur ; Jorgensen, S.B., Auteur . - 2008 . - pp. 659 - 668.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 659 - 668
Mots-clés : Fault location; least mean squares methods; power plants; principal component analysis Résumé : This paper presents and compares model-based and data-driven fault detection approaches for coal mill systems. The first approach detects faults with an optimal unknown input observer developed from a simplified energy balance model. Due to the time-consuming effort in developing a first principles model with motor power as the controlled variable, data-driven methods for fault detection are also investigated. Regression models that represent normal operating conditions (NOCs) are developed with both static and dynamic principal component analysis and partial least squares methods. The residual between process measurement and the NOC model prediction is used for fault detection. A hybrid approach, where a data-driven model is employed to derive an optimal unknown input observer, is also implemented. The three methods are evaluated with case studies on coal mill data, which includes a fault caused by a blocked inlet pipe. All three approaches detect the fault as it emerges. The optimal unknown input observer approach is most robust, in that, it has no false positives. On the other hand, the data-driven approaches are more straightforward to implement, since they just require the selection of appropriate confidence limit to avoid false detection. The proposed hybrid approach is promising for systems where a first principles model is cumbersome to obtain. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4470327&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 669 - 680
Titre : Dynamic simulator for a PEM fuel cell system with a PWM DC/DC converter Type de document : texte imprimé Auteurs : Song-Yul Choe, Auteur ; Jong-Woo Ahn, Auteur ; Jung-Gi Lee, Auteur Année de publication : 2008 Article en page(s) : pp. 669 - 680 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : DC-DC power convertors; PWM power convertors; power control; proton exchange membrane fuel cells Résumé : Polymer electrolyte membrane (PEM) fuel cells typically have low voltage, high current, terminal characteristics that cannot accommodate common electric loads like electric motors or power utility grids. Thus, a dc/dc converter is required to boost the output voltage of these power systems. Furthermore, the terminal characteristics are dependent on loads and operating conditions of the fuel cell system. The continuously changing power demand of an electric load requires dynamically replenishing the air and fuel, by properly maintaining humidity in the cell and efficiently rejecting the heat produced. These factors present important challenges for the design of reliable and durable power systems. We present new dynamic models for a fuel cell system and a pulsewidth modulation dc/dc converter with associated controls and integration. The model for the system consists of three subsystems that include an PEM fuel cell stack, an air supply, and a thermal system. Four different controllers were designed to control the air, the coolant, and the output voltage of the converter, and to optimize the power flow between the fuel cell and the output capacitor. The integrated model with its controls was tested using a real-time simulator that reduced computational time and facilitated the analysis of the interactions between loads and the fuel cell components and also allowed the optimization of a power control strategy. The responses of a static and dynamic load show that the power controls proposed can coordinate two energy sources, resulting in improved dynamics and efficiency. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505385&sortType%3Das [...] [article] Dynamic simulator for a PEM fuel cell system with a PWM DC/DC converter [texte imprimé] / Song-Yul Choe, Auteur ; Jong-Woo Ahn, Auteur ; Jung-Gi Lee, Auteur . - 2008 . - pp. 669 - 680.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 669 - 680
Mots-clés : DC-DC power convertors; PWM power convertors; power control; proton exchange membrane fuel cells Résumé : Polymer electrolyte membrane (PEM) fuel cells typically have low voltage, high current, terminal characteristics that cannot accommodate common electric loads like electric motors or power utility grids. Thus, a dc/dc converter is required to boost the output voltage of these power systems. Furthermore, the terminal characteristics are dependent on loads and operating conditions of the fuel cell system. The continuously changing power demand of an electric load requires dynamically replenishing the air and fuel, by properly maintaining humidity in the cell and efficiently rejecting the heat produced. These factors present important challenges for the design of reliable and durable power systems. We present new dynamic models for a fuel cell system and a pulsewidth modulation dc/dc converter with associated controls and integration. The model for the system consists of three subsystems that include an PEM fuel cell stack, an air supply, and a thermal system. Four different controllers were designed to control the air, the coolant, and the output voltage of the converter, and to optimize the power flow between the fuel cell and the output capacitor. The integrated model with its controls was tested using a real-time simulator that reduced computational time and facilitated the analysis of the interactions between loads and the fuel cell components and also allowed the optimization of a power control strategy. The responses of a static and dynamic load show that the power controls proposed can coordinate two energy sources, resulting in improved dynamics and efficiency. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505385&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 681 - 689
Titre : High-performance algorithms for drift avoidance and fast tracking in solar MPPT system Type de document : texte imprimé Auteurs : Pandey, A., Auteur ; Dasgupta, N., Auteur ; Mukerjee, A.K., Auteur Année de publication : 2008 Article en page(s) : pp. 681 - 689 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : DC-DC power convertors; mathematical analysis; photovoltaic power systems Résumé : The power available at the output of solar arrays keeps changing with solar insolation and ambient temperature. Expensive and inefficient, the solar arrays must be operated at maximum power point (MPP) continuously for economic reasons. Of the numerous algorithms for this purpose, perturb and observe (P&O) is a standard. A derivative of gradient ascent method used in the optimization theory, this algorithm introduces a tradeoff between tracking and dynamic performance. This algorithm also has a tendency to drift the system away from the MPP as atmospheric conditions change. With continually changing atmospheric conditions, these inadequacies lead to poor utilization of solar arrays. This paper addresses both the issues. A variable-step-length algorithm is proposed to eliminate the tradeoff. The drift is minimized by evaluating the entire trend in a power versus voltage curve. Analytical results, validated on a prototype system show excellent performance. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4459702&sortType%3Das [...] [article] High-performance algorithms for drift avoidance and fast tracking in solar MPPT system [texte imprimé] / Pandey, A., Auteur ; Dasgupta, N., Auteur ; Mukerjee, A.K., Auteur . - 2008 . - pp. 681 - 689.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 681 - 689
Mots-clés : DC-DC power convertors; mathematical analysis; photovoltaic power systems Résumé : The power available at the output of solar arrays keeps changing with solar insolation and ambient temperature. Expensive and inefficient, the solar arrays must be operated at maximum power point (MPP) continuously for economic reasons. Of the numerous algorithms for this purpose, perturb and observe (P&O) is a standard. A derivative of gradient ascent method used in the optimization theory, this algorithm introduces a tradeoff between tracking and dynamic performance. This algorithm also has a tendency to drift the system away from the MPP as atmospheric conditions change. With continually changing atmospheric conditions, these inadequacies lead to poor utilization of solar arrays. This paper addresses both the issues. A variable-step-length algorithm is proposed to eliminate the tradeoff. The drift is minimized by evaluating the entire trend in a power versus voltage curve. Analytical results, validated on a prototype system show excellent performance. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4459702&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 690 - 700
Titre : Simulation of a wind turbine with doubly fed induction generator by FAST and simulink Type de document : texte imprimé Auteurs : Fadaeinedjad, R., Auteur ; M. Moallem, Auteur ; Moschopoulos, G., Auteur Année de publication : 2008 Article en page(s) : pp. 690 - 700 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Aerodynamics; asynchronous generators; power system simulation; wind turbines Résumé : In order to fully study the electrical, mechanical, and aerodynamic aspects of a wind turbine with a doubly fed induction generator, a detailed model that considers all these aspects must be used. A drawback of many works in the area of wind turbine simulation is that either a very simple mechanical model is used with a detailed electrical model, or vice versa. Hence, the effects of interactions between electrical and mechanical components are not accurately taken into account. In this paper, three simulation programs - TurbSim, FAST, and Simulink - are used to model the wind, mechanical and electrical parts of a wind turbine, and its controllers. Simulation results obtained from the model are used to observe the interaction of all three factors affecting the operation of a wind turbine system. For example, it is shown how an electrical disturbance can cause dangerous tower vibrations under high speed and turbulent wind conditions, which may not be feasible using a simple model of the wind and wind turbine. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457821&sortType%3Das [...] [article] Simulation of a wind turbine with doubly fed induction generator by FAST and simulink [texte imprimé] / Fadaeinedjad, R., Auteur ; M. Moallem, Auteur ; Moschopoulos, G., Auteur . - 2008 . - pp. 690 - 700.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 690 - 700
Mots-clés : Aerodynamics; asynchronous generators; power system simulation; wind turbines Résumé : In order to fully study the electrical, mechanical, and aerodynamic aspects of a wind turbine with a doubly fed induction generator, a detailed model that considers all these aspects must be used. A drawback of many works in the area of wind turbine simulation is that either a very simple mechanical model is used with a detailed electrical model, or vice versa. Hence, the effects of interactions between electrical and mechanical components are not accurately taken into account. In this paper, three simulation programs - TurbSim, FAST, and Simulink - are used to model the wind, mechanical and electrical parts of a wind turbine, and its controllers. Simulation results obtained from the model are used to observe the interaction of all three factors affecting the operation of a wind turbine system. For example, it is shown how an electrical disturbance can cause dangerous tower vibrations under high speed and turbulent wind conditions, which may not be feasible using a simple model of the wind and wind turbine. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4457821&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 701-707
Titre : Parallel operation of battery power modules Type de document : texte imprimé Auteurs : Chin-Sien Moo, Auteur ; Kong Soon Ng, Auteur ; Yao-Ching Hsieh, Auteur Année de publication : 2008 Article en page(s) : pp. 701-707 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Battery management systems Résumé : Operating batteries in parallel improves the battery power system management and resolves the problems of conventional battery banks that arrange batteries in series. The discharging currents of the batteries are independently controlled, but coordinated to provide a full amount of the load current. Batteries connected in parallel do not suffer from charge imbalance, and thus, can avoid being overcharged or overdischarged. Sophisticated discharging profiles can be realized to efficiently utilize the available stored energy in batteries. Some of the batteries may take rest or be isolated from the system for the open-circuit measurement during the operation period, thus, facilitating the estimation of the state-of-charge and the evaluation of state-of-health. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458231&sortType%3Das [...] [article] Parallel operation of battery power modules [texte imprimé] / Chin-Sien Moo, Auteur ; Kong Soon Ng, Auteur ; Yao-Ching Hsieh, Auteur . - 2008 . - pp. 701-707.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 701-707
Mots-clés : Battery management systems Résumé : Operating batteries in parallel improves the battery power system management and resolves the problems of conventional battery banks that arrange batteries in series. The discharging currents of the batteries are independently controlled, but coordinated to provide a full amount of the load current. Batteries connected in parallel do not suffer from charge imbalance, and thus, can avoid being overcharged or overdischarged. Sophisticated discharging profiles can be realized to efficiently utilize the available stored energy in batteries. Some of the batteries may take rest or be isolated from the system for the open-circuit measurement during the operation period, thus, facilitating the estimation of the state-of-charge and the evaluation of state-of-health. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458231&sortType%3Das [...]
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 708 - 713
Titre : An improved battery characterization method using a two-pulse load test Type de document : texte imprimé Auteurs : Coleman, M., Auteur ; Hurley, W.G., Auteur ; Chin Kwan Lee, Auteur Année de publication : 2008 Article en page(s) : pp. 708 - 713 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Lead acid batteries; lithium; testing Résumé : It is very important to have the ability to determine the available capacity, the state of charge (SoC), and the state of health (SoH) of a battery; this ensures that the battery has the available power for the system requirements. A battery is aged by charging and discharging cycles; this process degrades the chemical composition of the battery. An undercharged battery has sulphation and stratification effects that shorten the lifetime of the battery. Overcharging causes gassing and water loss. This paper describes a novel two-pulse test to determine the AHC, SoC, and SoH of a valve regulated lead acid (VRLA) and a lithium ion battery. These parameters are related to the voltage drop after each pulse of current discharge. The first pulse stabilizes the battery relative to its previous history, and the second pulse establishes the parameters. The new approach is fully validated by experiment. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458229&sortType%3Das [...] [article] An improved battery characterization method using a two-pulse load test [texte imprimé] / Coleman, M., Auteur ; Hurley, W.G., Auteur ; Chin Kwan Lee, Auteur . - 2008 . - pp. 708 - 713.
Energy conversion
Langues : Anglais (eng)
in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 708 - 713
Mots-clés : Lead acid batteries; lithium; testing Résumé : It is very important to have the ability to determine the available capacity, the state of charge (SoC), and the state of health (SoH) of a battery; this ensures that the battery has the available power for the system requirements. A battery is aged by charging and discharging cycles; this process degrades the chemical composition of the battery. An undercharged battery has sulphation and stratification effects that shorten the lifetime of the battery. Overcharging causes gassing and water loss. This paper describes a novel two-pulse test to determine the AHC, SoC, and SoH of a valve regulated lead acid (VRLA) and a lithium ion battery. These parameters are related to the voltage drop after each pulse of current discharge. The first pulse stabilizes the battery relative to its previous history, and the second pulse establishes the parameters. The new approach is fully validated by experiment. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4458229&sortType%3Das [...]
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