三相SPWM逆变器的谐波分析及其抑制策略

Harmonic Analysis of Three-Phase SPWM Inverter and its Inhibition Scheme

对三相电压型SPWM逆变器输出电压和电流谐波及其产生规律进行了讨论,并提出了一种新的易于工程实现的谐波抑制策略,该方法通过正确选择载波频率和在正弦调制波上叠加一个三次波使之成为鞍形波,产生相应的SPWM波形来控制逆变器开关器件的通断从而改善输出波形。数学分析表明有利于降低输出电压THD(波形畸变系数)、改善谐波电流损耗和转矩特性,仿真结果证明了这些措施的有效性和实用性。

This paper discusses the harmonics of output voltage and current of three-phase voltage SPWM inverter and its generating hales, and presents a kind of new harmonic inhibition scheme which is ease to achieve. This method can produce corresponding SP-WM waveform to control the switch of inverter and then improve output waveform by selecting the correct carrier frequency and saddle wave. Mathematics analysis proves that this method can reduce waveform distortion factor of output voltage THD, improves harmonic current loss and torque characteristics. These measures are effective and practical by proving proved by simulation results.