基于T型滤波器的并网矩阵变换器稳定性分析

针对风力发电并网矩阵变换器PWM信号开关频率较低、输出电流中谐波含量较大的状况，在并网变换器网侧采用T型滤波器取代典型的电感滤波器以抑制谐波电流．构建了基于T型滤波器的三相并网矩阵变换器系统模型，分析了其稳定性，阐述了基于并网输出电流和滤波器电容电流的双闭环控制策略，并通过仿真对其有效性和可行性进行了验证．结果表明：采用该控制策略实现了系统的稳定运行，且输出电流正弦性好，谐波含量小．

Stability Analysis of Grid-connected Matrix Converter Based on T-filter

In view of the fact that the grid-connected matrix converter in wind power generation system has a low PWM switching frequency and a large harmonic content in output current,this paper proposes that the typical induc-tance filter in the grid side of grid-connected matrix converter should be replaced by T-filter to restrain the harmonic current.A T-filter-based system model is built for the three-phase grid-connected matrix converter and its stability is analyzed.In addition,a double-loop control strategy based on the grid-connected output current and the filter capacitor current is presented,and its validity and feasibility are tested with simulation.The results indicate that the control strategy can ensure that the system be operated stably,with fine sinusoidal output current and small harmonic content.