基于同步旋转坐标系下DFT谐波检测方法在APF中的应用

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

针对三相有源电力滤波器(APF)选择性谐波补偿的实现问题,提出了一种基于同步旋转坐标系离散傅里叶变换(DFT)的谐波检测方法。首先,将负载电流信号从abc坐标系变换到dq坐标系;然后,对dq坐标系下的信号进行了DFT变换、解耦和反变换;再将dq坐标系下的信号反变换回abc坐标系;最后,对所提出的谐波检测方法在Matlab/Simulink环境下搭建了仿真模型。仿真及研究结果显示,该谐波检测方法具有较快的动态响应速度。

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.