基于FBD谐波检测的并联混合型有源电力滤波器的研究

o fast and effectively detect harmonic current of power system ,FBD method is proposed .Compared with method which is based on instantaneous reactive power ,FBD method has no complex transformation and transformation ,it can be used to detect harmonic current for single-phase、three-phase three-wire and three-phase four-wire system. But FBD method needs a low-pass filter to extract the DC current ,it causes delay and phase-shifting problems ,to solve these problems ,this paper presents a real-time sliding window to extract the DC current instead of low-pass filter .At the same time , shows the principle of hybrid active power filter ,and corresponding mathematical model is established .Finally ,take a new composite control strategy .Simulation results show correctness of the detection and effectiveness of the new composite control strategy .