中文摘要：

小波变换以其良好的时频局部化特性在电力系统中得到了广泛的应用,包括在谐波分析方面。但即使是时频窗面积最小的Morlet小波也存在频谱混叠现象,使得单纯利用小波变换系数的幅值无法对谐波准确检测。本文提出了基于Morlet复小波幅值和相位信息相结合的谐波、间谐波检测方法。首先利用a-S（a）曲线粗略确定包含被测信号信息的尺度范围,然后利用这些尺度上的小波变换系数的相位信息来实现谐波、间谐波频率的检测,最后根据检测出的频率确定特征尺度,进而确定被测信号的幅值。与FFT方法和传统的尺度-幅值法相比,该方法能够克服频谱泄漏现象,且能够区分频率相近的信号成分,提高了谐波、间谐波的检测精度。通过Matlab软件进行仿真,结果验证了该算法的正确性。

英文摘要：

Because of excellent time-frequency characteristic,wavelet transform can be used in power system,including harmonic analysis.But only applying amplitude of wavelet transform coefficients can not realize accurate harmonic detection because of spectrum aliasing phenomenon even in the Morlet complex wavelet.Amplitude-phase information of Morlet complex wavelet transform is proposed to detect harmonic and interharmonic in this paper.Scale range including the detected signal information can be approximately confirm based on a-S（a）,then phase information can be used to detect harmonic and interharmonic frequency in these scale,in the end characteristic scale and amplitude can be gotten.Comparing with FFT and scale-amplitude algorithm, the method can avoid the spectrum leakage and distinguish signal of closely frequency,improving the precision of harmonic and interharmonic measurement.The result of simulation through Matlab prove the right of this algorithm.