基于柔性电流源的三相不平衡电压补偿方法及应用

在以消弧线圈接地为主的配电网中,由于线路换位不合理等因素导致的三相电压不平衡普遍存在。不平衡电压的存在会导致系统过电压和消弧线圈补偿度过高等问题,严重影响系统运行安全。采用柔性电流源补偿的方法来解决电压不平衡问题,首先向系统注入补偿电流,根据系统不平衡电压变化来计算最终的补偿电流,并将最终补偿电流的幅值和相位发送给柔性电流源,实现补偿不平衡电压的目的。经过推导得出采用与消弧线圈上电流相位相反的电流来补偿会降低不平衡电压,同时给出了补偿算法的流程。仿真分析验证了补偿算法的有效性。

Three-phase Unbalanced Voltage Compensation Method Based on Flexible Current Source and Its Application

In distributed networks with arc-extinguish coil grounding,the unbalanced three-phase voltage caused by irrational line commutation etc.generally exists.The existence of unbalanced voltage leads to the problems of over-voltage and overcompensation of arc-extinguish coil,which seriously affects grid operation safety of the system.In this paper method using flexible current source to compensate is proposed to solve the problem.Firstly,the compensation current,whose phase and amplitude are transmitted to flexible current source through communication,is injected into system and final compensation current is calculated based on unbalanced voltage change to realize reducing unbalanced voltage.Through derivation this paper adopts the trial compensation current whose phase is reverse to that of arc-extinguish coil current to reduce unbalanced voltage,and process of compensation algorithm is provided.Simulation analysis verifies the effectiveness of the compensation algorithm.