三相四线制背靠背变换器零电压开关技术

Zero-voltage-switching Technique for Three-phase Four-wire Back-to-back Converter

提出了一种零电压开关ZVS(zero-voltage-switching)三相四线制背靠背BTB(back-to-back)变换器拓扑及齐边沿脉宽调制EA-PWM(edge aligned pulse width modulation)方法,辅助开关仅需要在每个开关周期内动作一次,就可以实现BTB变换器中所有功率器件的零电压开通。介绍了电路拓扑及调制方法,进行了阶段分析,并推导出了零电压开关条件。最后在一台50 kVA的绝缘栅双极型晶体管IGBT(insulated gate bipolar transistor)实验样机进行了验证。

In this paper,the topology of a zero-voltage switching(ZVS)three-phase four-wire back-to-back(BTB)converter and its edge aligned pulse width modulation(EA-PWM)scheme are proposed.Under the novel EA-PWM scheme,the auxiliary switch only needs to operate once in each switching period so that all the power devices in the BTB converter can realize ZVS operation.The circuit topology and its modulation method are introduced,and stage analysis is performed.In addition,the ZVS conditions are derived.Finally,the proposed topology and EA-PWM scheme were verified on a 50 kVA IGBT experimental prototype.