三相高功率因数PWM变换器可逆运行研究

Research on Bidirectional Operation of a Three-Phase High Power Factor Converter

研究了一种基于空间矢量调制的三相PWM双向变换系统的控制策略,该系统在整流和有源逆变工作模式下均可改善电网侧的单位功率因数。建立了两相同步旋转坐标系下的变换器低频数学模型;在分析变换器能量双向流动的基础上给出其控制方法,利用电压调节器控制变换器的功率流向,实现变换系统跟随其直流侧电压的变化在整流和有源逆变状态之间的无缝切换。这种电流电压调节器的设计方法和缓起动控制,使系统在整流和逆变模式下均可获得良好的动静态性能。最后给出了实验验证结果。

A three-phase PWM bidirectional converter system with space vector regulated is researched. The system is operated with unity power factor in the side of AC line no matter in rectifier mode or active inverter mode. Low frequency model of the converter is built in the two-phase rotating reference frame. Control principle is proposed based on the analysis of the power flow in the both operation mode mentioned. The system switches automatically and smoothly between the rectifier and inverter mode, according to the value of the DC voltage with the power flow controlled through the voltage regulator. Current and voltage regulation principle and soft startup control are researched, based on system control diagram, both static and dynamic performance achieved as a result. Experimental results are given to verify the proposed analysis and design at the end of the paper.