摘要
正确提取电网谐波是进行电能质量分析的前提,利用小波分析能将电压或电流等信号分解为基波信号和高次谐波信号。分析了离散小波混叠的物理本质,提出一种新的混叠抑制方法,克服了现有抗混叠方法计算量大的缺点,并通过MATLAB进行仿真,表明该方法可以有效消除谐波检测中的小波混叠现象,将信号中不同频率的谐波有效地提取出来,有利于进行电力系统谐波信号精确分析。
Exactly decomposing the harmonic component is a prerequisite to power quality analysis.Wavelet analysis can decompose voltage signals or current signals to fundamental wave and higher harmonic waves.This paper analyzes the physical essence of aliasing in discrete wavelet at first,then propose a new method to reduce aliasing.The new method demands less calculation amount than existing methods used to reduce aliasing,and simulation with MATLAB was passed.The simulation result proves that it can effectively eliminate aliasing in wavelet transform and the different harmonic waves can be separated,and provide a vigorous means for power system harmonic analysis.
出处
《电气开关》
2012年第5期22-25,29,共5页
Electric Switchgear
关键词
电力系统
小波变换
小波混叠
谐波检测
power system
wavelet transform
wavelet aliasing
harmonic detection
