Detecting Method for Harmonics and Reactive Currents in Single-phase Circuits

In order to meet the demand of instantaneous harmonics and reactive currents in single phase circuit,a new method is proposed for real time detection of harmonics and reactive currents in single phase circuit.The method solved the problem of real time harmonics and reactive currents detecting successfully and it can be realized easily.The error effect of phase lock loop(PLL)in the method is analyzed theoretically in detail.In order to compensate the delay of the low pass filter,the harmonics are used as feedback to accelerate the speed of dynamic response.The simulation illustrates the effectivity of the proposed method.