基于基波与谐波正负序提取方法的动态电压恢复器补偿策略

摘要

提出一种新型补偿策略应用于动态电压恢复器(DVR).该策略以瞬时无功理论为基础,采用含分离模块的多坐标系旋转变换(多dq旋转变换)来提取出波形中的基波正负序分量和谐波正负序分量,从而对各个分量进行独立的补偿控制和参数调节.使用新型补偿控制策略后,DVR的动态响应速度更快,稳态补偿精度更高,dq控制分量波动更小.为验证其有效性,在MATLAB/Simulink下建立级联式DVR仿真模型,并进行了一系列仿真验证,稳态和暂态结果显示,在中压电网电压出现不对称、谐波和系统电压暂降等复杂工况时,DVR皆可以实现较好的补偿.%A compensation strategy is proposed for DVR(Dynamic Voltage Restorer),which,based on the theory of instantaneous reactive power, applies the multi dq rotate transform to extract the positive and negative sequence components and carries out the separate compensation control and parameter adjustment for each component. With the proposed strategy,the dynamic response of DVR becomes quicker,the compensation accuracy is higher,and the fluctuation of dq control components is smaller. The simulation model of cascaded DVR is built with MATLAB/Simulink and the static and transient simulative results validate its effectiveness under complex operating condition: unbalanced middle-voltage grid with harmonic and system voltage sags.