采用小波分析的滞环电流控制逆变器谐波分析

Harmonic Analysis for Hysteresis Current Controlled Inverter Using Wavelet Analysis

为了能实时发现逆变器输出波形的畸变和精确提取输出波形中的谐波分量,采用基于Gauss函数的一阶导数为小波函数的小波模极大值方法对逆变器输出电压波形畸变进行实时监测,采用谐波小波对输出电压的奇次谐波进行提取和分析。仿真结果表明,小波模极大值方法能够在时域里敏感地检测到输出波形的畸变,谐波小波能够精确提取出输出波形含有的各奇次谐波。这两种小波分析方法为研究先进谐波抑制策略提供了有力支持。

In order to discover the distortion of the inverter＇s output voltage on a real-time basis and to accurately extract harmonic components within the output waveform,the wavelet module maximum method,taking Gauss function＇s first derivative as wavelet function,was adopted to monitor the real-time of the waveform distortion of the inverter＇s output voltage. The harmonic wavelet was used to extract and analyze the odd-order harmonics of the output voltage. The simulation results show that,based on the wavelet module maximum,the distortion of output waveform can be detected effectively in time domain,and the harmonic wavelet can extract all odd-order harmonics included in output waveform. Above-mentioned two methods of wavelet analysis have laid a solid foundation for further study in advanced harmonic suppression strategy.