说明：  基于FFT的谐波检测,采用快速傅里叶算法后得到原始波形中各次分量的频率和幅值特性，从中可以直接观测出各次谐波分量的频率和幅值信息. 程序1采用快速傅里叶算法后得到原始波形中各次分量的频率和幅值特性图 程序2输入信号经过FFT变换得到的频谱特性图 程序3对输入信号进行采样，应用一维小波变换函数进行三层小波分析
(Based on FFT harmonic detection, the frequency and amplitude characteristics of each harmonic component in the original waveform are obtained by using fast Fourier algorithm, from which the frequency and amplitude information of each harmonic component can be directly observed In program 1, the frequency and amplitude characteristics of each component in the original waveform are obtained by using the fast Fourier algorithm The spectrum characteristic diagram of program 2 input signal through FFT transformation Program 3 samples the input signal and applies one-dimensional wavelet transform function to three-level wavelet analysis)