基于小波变换和小波包变换的间谐波检测

Interharmonic Detection Based on Wavelet Transform and Wavelet Packet Transform

通过研究小波变换中基函数选取和小波分解过程两个关键问题,针对小波变换在间谐波检测方面的应用,对比分析不同基函数的检测性能,重点分析小波变换与小波包变换对于稳态和暂态谐波的相位、幅值特性检测精度。仿真结果表明,小波包变换具有良好时频局部化特性能聚焦信号细节,选取dmey小波基函数的小波包分解方法可实现对电力系统中稳态或时变间谐波信号更精确的检测和分析,对于小波变换电力谐波检测中的实际应用具有指导意义。

The paper focuses on the two key issues of base function selection in wavelet transform and wavelet decomposition process.Targeting the application of the wavelet transform in interharmonic detection,this paper compares and analyzes the detection performance of different basis functions,and emphatically analyzes the detection accuracy of phase and amplitude characteristics of steady-state or transient harmonic signals with the wavelet transform and wavelet packet transform.The simulation results show that the wavelet packet transform has good time-frequency localization characteristics to focus on the details of the signals,and the wavelet packet decomposition method using dmey wavelet basis function can achieve more accurate detection and analysis of the steady-state or time-varying interharmonic signals in power system,which has guiding significance for the practical application of the wavelet transform in power harmonic detection.