并联型多重化三相四线有源电力滤波器综合控制策略研究

Integrated control strategy of three-phase four-wire shunt active power filter using multiple converters

为了提高大功率并联型有源电力滤波器的控制性能,谐波检测采用特定次谐波电流检测算法,能分别检测不对称谐波的正、负、零序分量,提高谐波检测的准确性和实时性。提出一种基于LCL滤波的多重化有源电力滤波器双闭环控制策略,该控制策略解决了变流器多重化主电路中的环流问题。采用LCL输出滤波器,不仅能有效地滤除主电路高频开关纹波,而且与传统的L滤波器相比,大大减少了电感量、提高系统的动态跟踪性能,并节约了成本。最后,搭建了系统仿真模型和实验样机,结果表明上述控制策略的正确性和可行性,系统谐波治理效果好。

In order to improve the control effect of high-power shunt active power filter, the paper uses detection algorithm for selective harmonic current in three-phase four-wire system. The algorithm can detect positive, negative and zero phase-sequence component of the random harmonic current, and can improve the accuracy and real-time of the harmonic current detection. At the same time, the paper presents a dual closed-loop control strategy to suppress the circulating current brought about by the multiple structure of the main circuit. The grid side filters use LCL-filter. Compared to traditional L-filter, the LCL-filter has better filter performance not only in effectively filtering the high frequency switching harmonics of the main circuit, but also in reducing the value of inductance, improving system dynamic performance and reducing the cost. Finally, the paper sets up a simulation model and an experimental prototype of the system, and the results show that the control strategy is correct and feasible, and harmonic treatment of the system is effective.