一种单相电路谐波电流检测的新方法

根据非线性负载的等效电路模型,以“当负载电流为周期电流时,负载电流与负载基波有功电流差的绝对值在一个周期内的积分值最小”为检测原理,提出了一种基于迭代算法的有源电力滤波器单相电路谐波电流检测方法．使用该方法先计算出产生基波有功电流的电阻部分对应的电导,则可求出基波有功电流,用负载电流减去基波有功电流,就得到实际要补偿的谐波及无功电流．该方法具有计算量非常小,实时性好,检测精度高等特点．理论分析与仿真研究证实了该方法的有效性．

A novel detecting method for harmonic current in single-phase circuit

According to the equivalent circuit model of non-linear load,and using "when load current is periodic function,the integral in a period for absolute value of the difference between the load current and fundamental active current is the least" as detecting principle,a harmonic current detecting method for single-phase active power filter based on iterative algorithm was proposed.By using it,the conductance corresponding to resistance part is determined at first which brings fundamental active current,then the fundamental active current can be calculated.The sum of harmonic and reactive currents which are ac-(tually compensated) can be obtained by using load current subtracting fundamental active current.It has the characteristics of very small calculating quantity,fine real-time performance and high detection precision.The validity of the method is proved by theoretical analysis and simulations.