一种电网间谐波检测新方法

提高间谐波检测精度的一个关键问题是如何减少谐波频谱泄漏对其造成的影响.提出一种新的"双阶段"间谐波检测方法,第一阶段基于加窗捅值FFT方法检测谐波分量,并将其从原信号中滤除掉;第二阶段以固定的采样频率对保留的样值信号进行FFT分析,在没有谐波频谱泄漏下扰的前提下提取间谐波分量.仿真结果表明:该方法不需要同步处理,计算量小,检测精度高,适于对间谐波的快速检测.

A New Method for Inter-harmonic Detection of Power Grid

A key problem for improving inter-harmonic detection precision is how to reduce the influence caused by harmonic spectral leakage. A "two-stage" novel method of inter-harmonics detection was presented. In the first stage, harmonics components were detected through window-interpolated FFT, and were filtered away from original signal. In the second stage, the reserved signal was analyzed through FFT with fixed sampling frequencies. The inter-harmonics components couhl be extracted under condition of no harmonic spectral leakage interference. The simulation results showed that the new method needed no synchronized process, and had advantages of smaller calculation amount but higher detection accuracy. The method is applicable to a rapid detection of inter-harmonics.