直接电流控制的SVG补偿不平衡电压的研究

Direct-current-controlled Static Var Generator for Voltage Imbalance Compensation

针对电能质量中的电压不平衡问题。提出了一种用静止无功发生器抑制公共连接点(PointofCommonCoupling,简称PCC)处不平衡电压的控制方法。本文将静止无功发生器控制为受负载端负序电压控制的电流源,以该补偿电流的作用来降低PCC处电压的不平衡度。文中分析了其补偿性能与各参数间的相互关系,介绍了PCC处负序电压的适时检测方法。仿真和实验结果表明,该方法可有效补偿电源或负载引起的电压不平衡问题,从而满足电力负荷对电网电压质量的要求。

In this paper,a direct-current-controlled Static Var Generator (SVG) is proposed to solve the voltage imbalance issue at the Point of Common Coupling(PCC).The SVG is operated as a current source controlled by the negative sequence voltage at the PCC.This controlled current can reduce the voltage imbalance factor at the PCC.The relationship between all the parameters and the compensating characteristics are analyzed in detail.And the negative sequence voltage decomposition method is then introduced.Simulation and experiment results verify the performance of the SVG in compensating voltage imbalance with the proposed control scheme.