基于小波与FFT的电网谐波检测改进方法研究  

The Research of Improving Harmonic Detection Methods Based on Wavelet Transform and FFT

作　　者：陈春玲[1] 梁伟伟[1] 许童羽[1] 王立地[1] 杨晨[1] 

机构地区：[1]沈阳农业大学信息与电气工程学院,沈阳110161

出　　处：《农业科技与装备》2009年第4期76-78,共3页Agricultural Science & Technology and Equipment

基　　金：辽宁省教育厅高校科研A类项目(2008635)

摘　　要：谐波检测的准确性直接影响对电网谐波污染状况的评估以及抑制措施的实施。本研究采用小波变换与快速傅里叶变换(FFT)相结合的方法提高谐波检测的准确度,利用小波变化对电网模拟信号进行降噪处理,使其尽可能接近原始信号的波形;利用FFT对去噪以后的信号进行分析,提取各次谐波含量;最后,利用matlab FFT工具进行仿真,仿真结果表明:该方法适合在谐波检测系统或装置中应用。The accuracy of harmonic detection has a direct impact on assessment and the implementation of restraining to the pollution of harmonic. In this paper, method to the combination of wavelet transform and fast Fourier transform （FIT） will improve the accuracy of harmonics testing. Firstly, the network analog signals collected are denoised by wavelet so as to get the waveform as close as possible to the original signals. Secondly, after analysis the denoised signals by FFT, the harmonic contents are extracted. Comparison the Matlab simulation testing results of noised and denoised, the level of harmonic signals after denoised is closer to the original signals. The mean of denoising enhances the accuracy of harmonic detection, as well as such a method to the combination of wavelet transform and fast Fourier transform （FFY） will apply to the harmonic detection systems or devices.

关 键 词：谐波检测 小波去噪 FFT MATLAB仿真 

分 类 号：TM711[电气工程—电力系统及自动化]