Lower harmonic distortion at low switching frequency requires optimal pulse patterns. But it cannot be directly used in high performance systems. A stator flux trajectory tracking control (FTTC) system is studied, and a pulse width modulation (PWM) correction method is proposed. Based on this method, dynamic modulation errors and high overcurrents as the operating conditions change are discussed. Furthermore, high performance closed-loop control of optimal PWM based on FTTC with a self-controlled machine model can be realized. Simulation results show that both fast dynamic response and low harmonics characteristic can be achieved at a low switching frequency of 200∽300 Hz. Its harmonic characteristic is more outstanding than that of model predictive direct control methods.
SONG Wen-xiang, JIANG Shu-hao, RUAN Zhi-yong, YANG Ying, RUAN Yi
. High performance close-loop control of optimal PWM based on stator flux trajectory tracking[J]. Journal of Shanghai University, 2015
, 21(1)
: 128
-140
.
DOI: 10.3969/j.issn.1007-2861.2014.03.021
[1] Geyer T, Papafotiou G, Morari M. Model predictive direct torque control—part I: concept, algorithm and analysis [J]. IEEE Transactions on Industrial Electronics, 2009, 56(6): 1894-1905.
[2] Geyer T. Model predictive direct current control: formulation of the stator current bounds and the concept of the switching horizon [J]. IEEE Industry Applications Magazine, 2012, 18(2): 47-59.
[3] Holtz J, Oikonomou N. Synchronous optimal pulsewidth modulation and stator flux trajectory control for medium-voltage drives [J]. IEEE Transactions on Industry Applications, 2007, 43(2): 600-608.
[4] Oikonomou N, Holtz J. Closed-loop control of medium-voltage drives operated with synchronous optimal pulsewidth modulation [J]. IEEE Transactions on Industry Applications, 2008, 44(1): 115-123.
[5] Holtz J, Oikonomou N. Fast dynamic control of medium voltage drives operating at very low switching frequency—an overview [J]. IEEE Transactions on Industrial Electronics, 2008, 55(3): 1005-1013.
[6] Holtz J, Qi X. Optimal control of medium-voltage drives—an overview [J]. IEEE Transactions on Industrial Electronics, 2013, 60(12): 5472-5481.
[7] Geyer T. A comparison of control and modulation schemes for medium-voltage drives: emerging predictive control concepts versus PWM-based schemes [J]. IEEE Transactions on
Industry Applications, 2011, 47(3): 1380-1389.
[8] 孙大南. 地铁车辆牵引电驱动系统控制关键技术研究[D]. 北京: 北京交通大学, 2012.
[9] Holtz J, Beyer B. The trajectory tracking approach—a new method for minimum distortion PWM in dynamic high-power drives [J]. IEEE Transactions on Industry Applications, 1994, 30(4): 1048-1057.
[10] Holtz J, Beyer B. Fast current trajectory tracking control based on synchronous optimal pulsewidth modulation [J]. IEEE Transactions on Industry Applications, 1995, 31(5): 1110-
1120.
[11] 马小亮. 概述低开关频率PWM变频的问题及解决办法[J]. 电气传动, 2009, 39(5): 3-9.
[12] 马小亮. 低开关频率中压传动的定子磁链轨迹跟踪控制综述[J]. 变频器世界, 2009, 12: 45-51.
[13] 符晓. 电励磁同步电机低开关频率控制技术研究[D]. 徐州: 中国矿业大学, 2011.
[14] 费万民, 张艳莉, 阮新波, 等. 三电平逆变器SHEPWM 非线性方程组的求解[J]. 中国电机工程学报, 2008, 28(6): 62-68.
[15] Holtz J, Oikonomou N. Estimation of the fundamental current in low-switching-frequency high dynamic medium-voltage drives [J]. IEEE Transactions on Industry Applications, 2008, 44(5): 1597-1605.
