电力系统广域测量中多采样率转换的研究

Study of multi-sample-rate signal conversion in wide area measurement for power system

广域测量系统对电网动态过程进行实时监测,为全网在线安全稳定分析和控制提供平台。但是,各测量点所用互感器并非同一型号,需要将多采样频率信号转换为同一采样频率。通过对不同采样频率信号的内插、抽取和凯赛窗低通滤波三者的级联,实现了任意分数倍采样频率的转换。在此基础上,提出了基于全波傅氏的数字窄带滤波算法。算例分析验证了所提方法的有效性和准确性。该算法在频率转换的同时能对信号进行有效、快速的滤波,实现了对采样信号不失真的频率归一化。

Wide Area Measurement System （WAMS） with real-time monitoring the power system dynamic process forms a platform for on-line security and stability analysis of the whole power grid. Because of the different sampling rates of current （voltage） transformers in WAMS, it is necessary to convert them to the same rate. Sampling rate conversion in a rational factor was realized through cascade connection of decimation, interpolation and low-pass filter. A digital constrictive band-pass filter algorithm based on full cycle Fourier algorithm was proposed. It can be proved that the method is validity through the illustrative example. This algorithm can not only obtain the useful signal from filter fast and effectively, but also realize the normalized sampling rate of signals without distortion.