基于Kalman滤波和短时自相关变换的电压暂降检测

作者：黄杰1,2,张晓峰1,2,姚文熙1,吕征宇1* 日期：2010-06-28/span> 浏览：3470 查看PDF文档

基于Kalman滤波和短时自相关变换的电压暂降检测
黄杰1,2,张晓峰1,2,姚文熙1,吕征宇1*
(1.浙江大学 电气工程学院，浙江 杭州 310027； 2.浙江大学 山特（伊顿）电力电子联合实验室,浙江 杭州 310027)

摘要：为了在含有谐波和噪声的电网中准确检测电压暂降，将卡尔曼滤波器和短时自相关变换结合起来，对相邻工频周期的采样信号做差，再进行短时自相关变换，准确检测到了电压扰动，采用卡尔曼滤波器对基波幅值和相位进行了估计；采用离线计算增益矩阵K的方式减小了卡尔曼递推算法的运算量，并在稳态时通过采用定常增益矩阵K达到了抑制滤波发散的目的，同时减小了所需的存储空间；Matlab仿真实验证实了此方法的有效性。
关键词：电压暂降；基波检测；卡尔曼滤波器；短时自相关算法
中图分类号：TM74文献标识码：A文章编号：1001-4551(2010)05-0051-05

Detection of voltage sag based on Kalman filter
and short time selfcorrelation transfer

HUANG Jie1,2, ZHANG Xiaofeng1,2, YAO Wenxi1, LV Zhengyu1
(1. College of Electrical Engineering, Zhejiang University, Hangzhou 310027, China;
2. Santak Joint Laboratory of Power Electronics, Zhejiang University, Hangzhou 310027, China)

Abstract: In order to detect voltage sag in power system which contains plenty of harmonics, the Kalman filter and short time selfcorrelation transfer were combined. The differential signal was gotten between sample value and that a period ago, then the differential signal was coped with the short time selfcorrelation transfer algorithm, which helps detect the voltage disturbances. After that estimating the amplitude and phase with Kalman filter, the coefficient matrix K offline was calculated, which reducing the calculated capacity remarkably. Using the const K when the state is steady, it not only prevent from filter instability , but also reduce the demand of storage space. The stimulation results show its validity and feasibility.
Key words: voltage sag; fundainental wave detection; Kalman filter; short time selfcorrelation algorithm