基于多采样率定时比较技术的并联有源滤波器

针对并联有源滤波器传统的定时比较控制法开关频率低、电流纹波大的问题,提出一种多速率采样定时比较控制方法,该方法对有源滤波器输出电流采用较负载电流更高的采样频率,在每个计算无功和谐波给定值的框架周期内对有源滤波器实现多次有效的控制,提高系统的控制性能。给出了该控制策略的理论依据和实现方法,分析比较了新方法与传统方法之间的特性差异。通过对双采样率系统的仿真和实验验证了本文所提方法的有效性。

Shunt Active Filter Based on Multirate Sampled Timer Comparison Technology

Traditional timer comparison control method for shunt active power filter induces a low switching frequency and a large current ripple.To address these problems,this paper proposes a novel multirate sampling timer comparison control strategy,which can improve the system’s control performance.Output current of active power filter is sampled much faster than load current,and this method can implement multiple effective controls in every frame period,while reactive power and harmonic current reference values are calculated just once.The characteristics of system with the proposed controller are investigated and compared with the traditional strategy.Simulation and experiment results of double sampling rate control demonstrate the effectiveness of the proposed method.