一种改进的无功及谐波电流检测方法

An Improved Method for Detecting Reactive and Harmonic Currents

有源电力滤波器的工作性能很大程度上取决于是否能够准确、实时地检测无功及谐波电流。针对单相系统瞬时无功与谐波检测算法复杂的问题,提出了一种改进的检测方法。不需要锁相环(PLL)和复杂的硬件电路,利用正交波形特性检测出电压相位,不仅减少了计算量,并且可根据需求分别检测出总谐波电流或特定次谐波的大小。该算法还能直接推广应用于三相三线制、三相四线制系统无功及谐波电流检测。

Detecting reactive and harmonic currents highly precise and real-time makes important influence on active power filter. In this paper, an improved method is proposed in order to detect the reactive and harmonic currents in single-phase power systems. It can detect the grid voltage phase angle based on the orthogonal characteristics without using the phase lock loop （ PLL ） and complex hardware circuit . The improved method can not only decrease the calculation capacity, but also detect the sum harmonic currents or the specific harmonic currents according to different requirements. It can be directly used in three-phase three-wire or three-phase four-wire systems to detect the reactive and harmonic current.