三电平PWM整流器的研究

The Study of Three-level PWM Rectifier

在大功率应用中,由于在达到相同性能情况下,两电平较三电平整流器开关频率高一倍,散热困难,对IGBT管的耐压要求较高,因此研究了一种中点箝位型三电平PWM整流器。通过对这种拓扑结构与双三电平变频器系统的研究,提出了基于电网电压虚拟磁链定向的SVPWM控制策略。通过仿真和实验研究结果表明,中点箝位型三电平整流器可以很好地稳定直流母线电压,提高整流器的功率因数,并对电流谐波进行抑制。

In the high-power applications,the switching frequency of the two-level rectifier is twice higher than the three-level rectifier in the situation of the same performance,and it’s difficult to reject the heat,besides the two-level rectifier requires a higher voltage of IGBT,therefore,a mid-point clamp-type three-level PWM rectifier is researched.By researching of the topology and back to back three-level converter system,the SVPWM control strategy based on virtual flux-oriented line voltage is proposed.Through simulation and experimental results indicate that the mid-point clamped three-level rectifier-type can improve the stability of the DC bus voltage and the power factor of rectifier,fur-thermore,the current harmonics is inhibited.