直流供电的三相电压源逆变器支撑电容的优化设计  

Optimal design of DC-link capacitor of three-phase voltage source inverter powered by DC supply

作　　者：彭威[1] 乔鸣忠[1] 蒋超 张志斌 PENG Wei;QIAO Ming-zhong;JIANG Chao;ZHANG Zhi-bin(College of Electrical Engineering,Naval Univ.of Engineering,Wuhan 430033,China)

机构地区：[1]海军工程大学电气工程学院,武汉430033

出　　处：《海军工程大学学报》2020年第6期60-66,共7页Journal of Naval University of Engineering

基　　金：国家自然科学基金面上项目(51877212;51807197)。

摘　　要：对于直流供电的三相电压源逆变器,通过估算和根据经验选取电容会导致严重的过设计,不利于节省空间和成本。为此,分析了直流侧支撑电容抑制直流母线高频谐波电流的机理,建立了永磁同步电机空间矢量脉宽调制下直流母线输入电流的模型,推导出直流母线高频谐波的最大幅值为输出相电流峰值,得到了电容电压和电流脉动关于调制比和负载的表达式,并给出了能减小直流母线高频谐波的电容选取方法。按照设计的电容参数搭建了仿真和实验平台,结果表明:所提的支撑电容选取方法能在有效抑制直流母线电流谐波的同时避免过设计。When the Three-phase voltage source inverter is powered by DC supply,traditional estimation and empirical methods to select capacitors may result in overdesign, and cause space and cost waste. Thus, the mechanism of DC-link capacitor for suppressing high frequency current harmonics was analyzed. The model of DC bus input current for permanent magnet synchronous motor(PMSM) under space vector pulse width modulation(SVPWM) was built to calculate the amplitude of the current harmonics on the DC bus. The expression of capacitor voltage and current ripple based on the modulation ratio and load was derived. Then, a specific method of capacitor design was proposed to reduce the high frequency harmonic current. The simulation and experiment platform were built, and the results indicate that the proposed DC-link capacitor selection method can effectively suppress the DC bus current harmonics while avoiding over-design.

关 键 词：直流母线高频谐波电流 支撑电容 永磁同步电机 空间矢量脉宽调制 

分 类 号：TM921.5[电气工程—电力电子与电力传动]