CAJ | 학술논문

环流抑制是逆变器可靠并联运行的关键技术，针对微电网中的共直流母线冗余并网逆变器的并联运行，提出了一种基于零序电压差补偿原理的零序环流控制方法。首先分析了并联逆变器间零序环流等价模型，根据单台逆变器的零序电流反馈量和无差拍电流控制方法直接得到并联逆变器间的零序电压差补偿量。然后通过调节该单台逆变器的零序电压使并联逆变器间的零序电压差接近零，实现抑制零序环流的目标。最后，仿真和实验结果验证了所提零序电压差补偿原理和零序环流控制方法的有效性。
배류억제시역변기가고병련운행적관건기술，침대미전망중적공직류모선용여병망역변기적병련운행，제출료일충기우령서전압차보상원리적령서배류공제방법。수선분석료병련역변기간령서배류등개모형，근거단태역변기적령서전류반궤량화무차박전류공제방법직접득도병련역변기간적령서전압차보상량。연후통과조절해단태역변기적령서전압사병련역변기간적령서전압차접근령，실현억제령서배류적목표。최후，방진화실험결과험증료소제령서전압차보상원리화령서배류공제방법적유효성。
Circulating current restraining is the key technology for the reliable operation of paralleled inverters. Based on the compensation principle of zero-sequence voltage difference, this paper proposed a zero-sequence circulating current control method for the redundant paralleled grid-tied inverters with common DC-bus in microgrids. Firstly, the equivalent circuit model of circulating current between paralleled inverters was analyzed, and the quantity of zero-sequence voltage compensation between inverters was obtained by the deadbeat current control method according to the zero-sequence current feedback of a single inverter. Then, the zero-sequence voltage difference between parallel inverters is close to zero by adjusting the zero-sequence voltage of a single inverter for restraining circulating current. Finally, simulation and experiment results verified the validity of the proposed control method to restrain the zero-sequence circulating current between paralleled inverters.