单相及三相电路谐波和无功电流的检测研究

Study on the Detection for Harmonics and Reactive Currents of Single-Phase and Three-Phase Circuits

提出了一种谐波及无功电流的直接检测法。用数学分析单相及三相电路中畸变电流,求出基波有功和无功电流,进而也可求得谐波电流。同时,引入了比例微分环节(PD)作为负反馈,以补偿低通滤波器(LPF)的延时,提高检测的动态响应速度。用MATLAB仿真的结果表明该检测法可行。

A method for direct-detecting the harmonic and reactive current is presented in this paper. The fundamental active and reactive current can be calculated by analyzing the distorted current of single-phase and three-phase circuits in the way of mathematics, so the harmonic current can also be obtained. Meanwhile this paper also proposes the PD negative feedback, which can compensate the inherent delay of LPF and quicken the dynamic response speed. Finally, the effectiveness of this detecting method is verified by MATLAB simulation.