基于正序基波提取器的改进型单相谐波检测算法研究

Research on the Improved Single Phase Harmonic Detection Method Based on Positive Sequence Fundamental Extractor

基于正序基波提取器的谐波检测算法具有结构简单、响应速度快以及检测精度较高等优点,但当系统中含有低次谐波、比例系数取值较大时,所提取基波电流的总谐波畸变率较大。为此,文章利用正序基波提取器选频特性,提出了一种逐级消除低次谐波的方法,以准确提取谐波信号,增强有源滤波器滤波效果。仿真实验结果验证了该算法的有效性和可行性。

There are some advantages of harmonic detection method based on positive sequence fundamental extractor, such as simple structure, fast response and higher detection accuracy and so on. Total harmonic distortion of extracted fundamental current will be higher as system contains some low-order harmonics and its proportion coefficient is larger. Hence, a method eliminating gradually low-order harmonic which utilize the frequency-selection characteristic of positive sequence fundamental extractor was proposed, which can extract harmonic signal accurately and enhance filtering effect of APF. Simulation results show the effectiveness and feasibility of this method.