随机SVPWM技术在背靠背变流系统中的研究与应用

Study and Application of Randomized Modulation SVPWM in Back-to-Back Converter

电力电子功率变换器产生的开关频率谐波是重要干扰源之一。为有效抑制开关频率谐波,除采用常用的低通滤波技术外,可以结合在电压空间矢量脉宽调制技术(SVPWM)中引入随机因子的方法,减小变换器输出电压、电流的开关频率谐波。通过对两种随机方案的理论分析与比较,开关周期随机化较脉冲位置随机化对抑制开关频率谐波有更好的效果。将随机因子引入开关周期中,形成随机周期电压空间矢量脉宽调制技术(RPSVPWM),并将其应用在背靠背变流器中。对有、无随机化的SVPWM的实验数据进行对比和分析,结果证实了该方法的有效性和可行性。

Switch frequency harmonic produced by converter is an important interfering source.Combining low-pass filter broadly used,random factor can be introduced to SVPWM in order to restrain switch frequency harmonic.Two randomized methods are analyzed and compared.Switch period randomization has better restraining effect than plus position randomization.Randomized period SVPWM（RPSVPWM） is used in back-to-back converter.The comparative analysis verifies the validity and feasibility of the scheme proposed in this paper.