STATCOM零输出无功时电容电压平衡控制方法研究

摘要

针对链式静止同步补偿器(STATCOM)中直流电容电压平衡的问题,在零输出无功的情况下,提出了给STATCOM每相输出指令电流中注入3次谐波电流的方法,使其产生一个扰动,分析了注入3次谐波后调制信号与直流侧电压的关系,基于有功矢量叠加的控制方法,加大了直流侧电容电压的可调控范围,同时在一定程度上提高了电压利用率,在实验平台上进行了验证,结果与理论分析一致.%In order to balance DC capacitor voltage of cascade static synchronous compensator (STATCOM) in the case of zero output reactive power,an idea which put each phase of STATCOM into third harmonic current is proposed and make it produce a disturbance,after injecting the third harmonics,the relationship between the DC voltage and modulation signal is analyzed.Based on the active control method of vector superposition,this method increases the DC side capacitor voltage regulating range,to a certain extent,the utilization rate of voltage is improved at the same time.Experiment is carried out on the experimental platform,the results are consistent with the theoretical analysis.