基于分数阶小波变换的电力系统谐波检测方法  

A Power System Harmonic Detection Method Based on Fractional Wavelet Transform

作　　者：窦嘉炜 杨小煜 杨晓忠[1] DOU Jiawei;YANG Xiaoyu;YANG Xiaozhong(College of Mathematics and Physics,North China Electric Power University,Changping District,Beijing 102206,China;China Electric Power Research Institute,Haidian District,Beijing 100192,China)

机构地区：[1]华北电力大学数理学院,北京市昌平区102206 [2]中国电力科学研究院有限公司,北京市海淀区100192

出　　处：《中国电机工程学报》2024年第3期872-879,I0002,共9页Proceedings of the CSEE

基　　金：国家自然科学基金项目(11371135)。

摘　　要：针对稳态和暂态谐波检测易受噪声干扰的问题,提出一种基于分数阶小波变换(fractional wavelet transform,FRWT)的电力系统谐波检测方法。首先,通过快速傅里叶变换(fast Fourier transform,FFT)检测出各频谱的频率,根据频率确定分解层数;其次,利用FRWT对信号进行分解和重构,实现基波与各次谐波分量的分离;最后,对各次谐波分量进行Hilbert变换(Hilbert transform,HT),获取各次谐波分量的频率和幅值检测结果以及暂态扰动的起止时刻。对多种谐波信号的仿真试验结果表明,FRWT方法可以有效实现对含噪信号中稳态和暂态谐波的检测,即使信噪比较低也能保证各项结果的检测精度,证明FRWT方法是检测谐波的一种有效新方法。Aiming at the problem that detection of stationary and transient harmonics is easily disturbed by noise,a harmonic detection method for power system based on fractional wavelet transform(FRWT) is proposed.First,the frequency of each spectrum is detected by fast Fourier transform(FFT),and the decomposition level is determined according to the frequency.Then,FRWT is used to decompose and reconstruct the signal,and the fundamental wave and each harmonic component in the signal are separated.Finally,Hilbert transform(HT) is performed on each harmonic component to obtain the frequency and amplitude detection results of each component and the start-end time of transient disturbance.The simulation results of various harmonic signals show that FRWT method can effectively detect the steady-state and transient harmonics in noisy signals and the detection accuracy of each result can be guaranteed even if the signal-to-noise ratio is low.It is proved that FRWT method is an effective new method to detect harmonics.

关 键 词：分数阶小波变换 小波变换 HILBERT变换 谐波检测 仿真试验 

分 类 号：TM71[电气工程—电力系统及自动化]