基于分层控制方法的微网谐波电压补偿策略研究

Research on Harmonic Voltage Compensation in Microgrid Based on Hierarchical Control Approach

针对多逆变器并联型微电网孤岛运行模式下的负载母线三相电压不平衡和谐波污染问题,本文提出一种基于两相静止αβ坐标系的微电网谐波电压分层控制策略。控制结构由本地DG控制器和微电网二次集中控制器组成。本地DG控制器通过改进型虚拟阻抗环和传统下垂控制策略实现微电网基波功率和补偿功率按额分配;微电网二次集中控制器产生电压不平衡和谐波补偿指令信号,并将其传送至DG本地控制器,通过电压电流控制器控制逆变器输出电压,实现微电网三相电压不平衡和谐波电压补偿。利用MATLAB/Simulink软件搭建仿真平台,验证了本文所提控制策略的正确性和优越性。

In order to deal with such issues as three-phase voltage unbalance and harmonic distortion at sensitive load bus in an islanded multi-inverter paralleled microgrid （MG）, a hierarchical control strategy is proposed based on two sta-tionaryαβframe to compensate harmonic voltage in this pa-per,in which the controller includes DG local controller and MG central controller.In addition,the DG local controller can allocate fundamental power and harmonic power of mi-crogrid by using advanced virtual impedance loop and tradi-tional droop control strategy.Furthermore,the secondary central controller of MG generates voltage unbalance and harmonic voltage compensation reference signals,and trans-fers it to the DG local controller to control the output volt-age of inverter. Then three-phase voltage unbalance and harmonic voltage compensation of mcirogrid are achieved. In the end,MTALB/Simulink software is used to build simu-lation platform to verify the validness and superiority of the proposed contral strategy.