不平衡工况下井下STATCOM控制策略研究

Research of STATCOM control strategy under underground unbalanced condition

针对井下不平衡工况会导致STATCOM控制性能变差、影响补偿效果的问题,提出采取改进开关函数法及负序电压前馈控制策略,让STATCOM发出一个与系统负序电压大小和相位都相等的负序电压,来补偿系统负序电压,保证了STATCOM在不平衡工况下的正常运行。仿真结果表明,该控制策略起到了抑制负序电流的作用,有效克服了三相不平衡的影响。

For problem that underground unbalanced condition will result in poor control performance of STATCOM, affecting compensation effect, the paper proposed a control strategy adopting improved switch function method and negative sequence voltage feedforward, made the STATCOM issue a negative sequence voltage whose magnitude and phase are equal to negative sequence voltage of the system to compensate for the negative sequence voltage of the system, so as to ensure normal operation of STATCOM under unbalanced condition. Simulation results show that the control strategy can inhibitnegative sequence current, and effectively overcome impact of three-phase unbalance.