大功率三相电流型晶闸管SVPWM整流器多桥并联技术

Multi-Bridge Parallel Technique of Three-Phase High Power SVPWM SCR-CSR

研究了一种新的三相电流型PWM整流器(CSR)的拓扑结构及其多桥并联技术。每个并联的整流桥单元均采用普通三相晶闸管(SCR)整流桥和直流回路串联的IGBT来共同完成SVPWM功能,多个整流桥单元采用一种基于矢量合成原理的并联技术。对于N个整流桥单元并联的大功率PWM整流器,任意整流桥单元都具有相同的SVPWM调制特性和相同的开关频率,而整个整流器的等效开关频率为单个整流桥单元的N倍。该方法不仅保留了传统SVPWM技术的所有优点,而且实现简单、成本低廉,是电流型PWM整流器实现低谐波、高效率、大功率的一种较好选择。

A new three-phase current source rectifier （CSR） topology and its multi-bridge parallel technique are studied in the paper. Every rectifier unit consisting of a traditional three-phase SCR-bridge and an IGBT connected in DC bus is modulated with space vector PWM （SVPWM） scheme. N rectifier units are paralleled directly and modulated based on space vector synthesis technique. So the modulation technique is the same with identical switching frequency for every rectifier unit, and the equivalent switching frequency of the whole system is N times of each unit. This new technique not only has the advantages of the traditional SVPWM technique, but also its realization is simple and its cost is low, which are very suitable for three-phase CSR to obtain good performances of low THD, high efficiency and high power capability.