SVPWM的调制函数与谐波分析研究

Study on Modulation Function and Harmonics of SVPWM

基于规则采样法,推导了SVPWM调制函数在线性调制区的解析表达式。其傅里叶分析表明,SVPWM实质是对在三相正弦波中注入零序分量的调制波进行规则采样的变型SPWM.在Matlab/Simulink环境下建模仿真。仿真结果表明,输出电压谐波主要集中在开关频率及其整数倍附近;随调制比增加,低次谐波增加,高次谐波减小,总畸变率降低。

Based on regular sampling method, the analytic expression of modulation function of space vector pulse width modulation （SVPWM） in the linear modulation range was deduced. The Fourier analysis demon- strates that SVPWM is essentially a variant of SPWM whose modulation wave was derived by adding a zero-se- quence component, in the form of sine wave segments, to the modulation wave of SPWM. A model was built in Matlab/Simulink environment. The simulation results show that harmonics of output voltage concentrate around integer multiples of carrier frequency, and higher modulation index yields higher low-order harmonics, lower high-order harmonics and a lower total harmonic distortion.