一种统一抑制双并联三相变流器中零序与相内环流的方法

This article proposes a unified pulsewidth modulation (PWM) strategy for suppressing both intraphase and zero-sequence circulating currents in two-parallel converters. The presented analytical modeling reveals that certain vector combinations inherently enable simultaneous control of both intraphase and zero-sequence circulating currents. Then, ten candidate vector sequences are constructed using those vector combinations. Since these vector sequences exhibit redundancy in the modulation region, we select the one with the lowest circulating current peak and RMS value. Subsequently, we develop a flowchart to implement the optimal vector sequences across the entire space vector plane. Quantitative comparisons with state-of-the-art PWM methods demonstrate that the proposed method not only reduces intraphase current but also achieves lower zero-sequence circulating current. Experimental validation confirms the effectiveness of the proposed method in suppressing both types of circulating currents.