基于改进Prony法的电力系统低频振荡快衰分量辨识

An Identification Method Based on Improved Prony for Fast Attenuate Component of the Power System Low-Frequency Oscillation

考虑到传统Prony算法对电力系统低频振荡模式中含有衰减较快的分量分析非常困难以及容易丢失衰减较快分量的问题,提出一种改进的快速衰减信号的提取方法——基于Givens变换的Prony分段分析法。该方法将采样时间划分为两个时段,首先分析第二时段求慢速衰减分量,然后分析第一时段求快速衰减分量。最后通过算例验证了该算法可以准确提取低频振荡模式中的快速衰减分量,同时也使得慢速衰减分量更加准确。

Considering that the traditional Prony algorithm is very difficult to analyze the fast attenuate component of the power system low frequency oscillation mode and the fast attenuate component can be missed easily,an improved method of extracting rapid attenuate signal is proposed which is called Prony segment analysis method based on Givens transform.This method divides the data acquisition time into two periods,and the second period is analyzed firstly to calculate the slow attenuate component,then the first period is analyzed for calculating the fast attenuate component.Numerical example proves that this algorithm can accurately extract fast attenuate component of low frequency oscillation mode,and also makes the slow attenuate component more accurate.