基于有功功率解耦的高能量密度单相PWM整流器

Research on Active Power Decoupling of Single-phase PWM Rectifier with High Power Density

单相PWM整流器直流侧含有2倍基波频率的纹波电能,输出电压随负载变化周期波动.传统方法采用无源滤波的方式,通过在直流侧添加大电容滤除低频谐波电流.但这种电容体积较大,不利于设计高能量密度的变换器.本文利用有功功率解耦的方法,利用直流电容存储纹波电能.可稳定输出电压,减小电容值.然后对控制策略进行研究,使用电压电流双闭环控制方法,实现系统快速响应和稳定特性.该方法通过仿真得到验证.

Single-phase PWM rectifier has second-order line frequency ripple power on DC-link, the output voltage will change with the load in period. The traditional way using passive filtering approach to filter low- frequency harmonic currents by adding high value capacitance to DC-link. The capacitance box has big size, which is disadvantage of designing high power density converter. This paper proposes an active power decou- pling method to store ripple power in DC-link capacitance. This way can balance the output voltage and reduce the value of capacitance. And then this paper has studied the control strategy, which make the system with quick response and stabilize by voltage-current double-loop controller. Finally, the method is validated by simulation.