T型三电平逆变器的共模干扰机理研究

摘要

The topology and operation modes of the T-type three-level inverter are analyzed to figure out the main causes for common mode ( CM) voltages.The Fourier expression of the common mode voltage under traditional si-nusoidal pulse width modulation ( SPWM) is deduced for harmonics analysis.A high frequency equivalent circuit of T-type three-level inverters for the common mode interference analysis is proposed.The simulation results with the proposed model coincide with the experiments results on the experimental prototype very well, which shows that the model is effective with acceptable accuracy.This study provides an important basis on CM interference suppression for T-type three-level inverters.%通过对T型三电平逆变器拓扑结构和工作模态的分析,得出逆变器共模电压的主要产生原因,推导了传统正弦PWM控制下共模电压的傅立叶表达式,并分析了其谐波成分.提出了T型三电平逆变器的共模传导电磁干扰高频等效电路模型,将基于该模型的共模电流频谱仿真结果和在T型三电平逆变器实验样机上获取的实测结果进行了对比分析,二者相互吻合,验证了本文提出的高频等效电路模型.本文的研究成果为T型三电平逆变器的共模电磁干扰抑制提供了重要的基础.