三相电压不对称时无功电流检测的改进dq法

Improved dq method used in reactive current detection in the case of unsymmetrical three-phase voltages

无功电流检测是实现无功补偿的关键环节,在三相电压不对称系统中,传统dq检测法会出现锁相不准确的情况,低通滤波器的使用也会影响到检测的实时性。改进的dq检测法对基波正序电压分量进行锁相,并基于电流平均值理论构建滤波环节,通过对电流有功分量和无功分量的积分延时,得到各自的直流分量。最后,在MATLAB中搭建仿真模型,仿真结果表明该方法的准确性和实时性。

unsymmetrical three-phase voltages, traditional dq method cannot lock phase accurately and the use of low-pass filter affects the real-time of detection. An improved dq method locks the fundamental positive sequence voltage component and constructs the filter block based on current average theory, this block can extract dc component through integral and delay for active component and reactive component. Finally, it builds a simulation model in MATLAB, the simulation results show the accuracy and real-time of the method.