Application of DFT-based harmonic detection method under synchronous reference frame in APF

JI Rui-feng， ZHOU Ming， SHEN Guang
（School of Electrical and Electronic Engineering， North China Electric Power University， Beijing 102206， China）

Abstract： Aiming at the realization of selective harmonic compensation for three-phase active power filter（APF），harmonic detection method based on discrete Fouries transform（DFT）was presented. Firstly，sampled load current signals were transformed from abc-frame to dq-frame；then，the signals were transformed from time-domain into frequency-domain，decouple and transformed back to time domain under dq-frame；the concerned parts were inverted into abc-frame. Finally，simulation experiment has been conducted under Matlab/Simulink environment. Simulation results verify the proposed method's fast response speed.
Key words： active power filter（APF）； selective harmonic compensation； harmonic detection； discrete Fouries transform（DFT）； synchronous reference frame