谐振直流环节逆变器缓冲回路无功能量传输损耗优化的改进调制策略  

A Modified Modulation Strategy for Optimizing the Transmission Loss of Reactive Energy in the Snubber Circuit of Resonant DC Link Inverter

作　　者：褚恩辉[1] 周越 陈志方 宋奇 张洋 CHU Enhui;ZHOU Yue;CHEN Zhifang;SONG Qi;ZHANG Yang(School of Information Science&Engineering,Northeastern University,Shenyang 110819,Liaoning Province,China)

机构地区：[1]东北大学信息科学与工程学院,辽宁省沈阳市110819

出　　处：《中国电机工程学报》2020年第22期7420-7430,共11页Proceedings of the CSEE

摘　　要：针对谐振直流环节逆变器缓冲回路在换流时无功能量传输损耗大这一问题,文中在一种并联谐振直流环节逆变器的基础上提出一种改进调制策略。与原调制策略相比,该调制策略不仅可以实现逆变桥、谐振单元开关管的软开关,而且可将缓冲回路的动作频率降低了1/3,降低了缓冲回路的导通损耗以及辅助开关管的开关损耗。同时可避免换流时缓冲回路的谐振电流与换流时刻的负载电流相叠加,从而可有效降低缓冲回路在换流时的无功能量传输损耗及辅助开关管的电流应力。在改进调制策略下,根据不同工作模式下的等效电路图,分析该逆变器的工作原理、软开关实现条件及最佳参数设计方法。最后使用绝缘栅双极型晶体管(insulated gate bipolar transistor,IGBT)作为开关器件制作一台10kW、10k Hz样机,通过实验验证该调制策略的有效性。In order to solve the problem that the transmission loss of reactive energy in the snubber circuit of resonant DC link inverter is large, this paper proposed a modified modulation strategy based on a parallel resonant DC link inverter. Compared with the original modulation strategy, this modulation strategy can not only realize the soft switching of inverter bridge and resonant unit switches, but also reduce the operating frequency of snubber circuit by 1/3, reducing the conduction loss of snubber circuit and switching loss of auxiliary switches. At the same time, it can avoid the superposition of resonance current and load current at the commutation moment in the snubber circuit, so as to effectively reduce the transmission loss of reactive energy and the current stress of auxiliary switches. According to the equivalent circuits of different operating modes under the modulation strategy, the paper analyzed the operating principle, soft-switching conditions, and optimal parameter design methods of the inverter. Finally, a 10 kW-10 kHz prototype with insulated gate bipolar transistor(IGBT)-based switches was built. The effectiveness of the modulation strategy was verified by experiment. Experimental results were given to demonstrate the validity and features of the inverter under this modulation strategy.

关 键 词：并联谐振直流环节逆变器 缓冲回路 无功能量传输损耗 零电流开关 零电压开关 

分 类 号：TM46[电气工程—电器]