新型低压大电流三相PWM整流器分析

摘要

对于一些电焊机或快速充电等低压大电流系统的应用场合,为了抑制交流侧谐波畸变率,多采用传统的三相电流型PWM整流器作为该变换器的拓扑结构,但是,该结构存在控制方法复杂、直流滤波电感庞大等缺点.针对传统变换器的这些不足,研究了一种新的三相Buck型整流器拓扑结构,并对其工作原理、控制方法、控制器的设计进行详细分析阐述,理论分析表明该结构控制简单、易于实现.最后,通过仿真验证了该结构抑制交流侧谐波畸变率、改善功率因数的有效性,以及提高变换器功率密度和快速响应能力的可行性.%In order to restrain the harmonic distortion in AC side,traditional three-phase current pulse width modulation (PWM)rectifier is usually used in application scenarios with low voltage and high current system,such as electric welding machine and quick charger.However,this structure has the disadvantages of complex control,large DC filter inductance,etc.In order to overcome these defects,a new topological structure of three-phase Buck rectifier is studied,and its working principle,control method and controller design are analyzed in detail.Theoretical analysis shows that this structure is simple and easy to implement.At last,the simulation results demonstrate that this structure can restrain harmonic distortion,improve power factor,and enhance the power density and fast response capability of converter.