阶梯波合成级联型多电平逆变器功率均衡策略  

Power Balance Strategy for Staircase Waveform Synthesis of the Cascaded Multilevel Inverter

作　　者：王学华[1] 阮新波[1] 王蓓蓓[1] 张欣[1] 孙宜峰[1] 

机构地区：[1]南京航空航天大学自动化学院,江苏省南京市210016

出　　处：《中国电机工程学报》2008年第30期12-19,共8页Proceedings of the CSEE

摘　　要：首先指出在波形质量要求相同的条件下,Ⅲ型级联多电平逆变器所需级联单元个数最少。接着讨论了3种级联多电平逆变器功率均衡问题,指出I型级联单元数低于7时,宜采用循环脉冲实现功率均衡,高于7时,宜采用调整开关角的方式实现功率均衡;Ⅱ型级联多电平逆变器只能通过调整开关角实现功率均衡,由于开关组合方式冗余,Ⅱ型存在多组功率均衡方程组,而通过计算发现,2单元Ⅲ型级联多电平逆变器无法实现功率均衡。最后通过一台单相容量为2kVA的原理样机对3单元Ⅱ型级联多电平逆变器的均衡策略进行了实验验证。Firstly, it points out that the Ⅲ-type cascaded multilevel （ML） inverter is the best topology, when outputs the same quality voltage. Secondly, the swapping pulse power balance strategy is proved to be better for the I-type cascaded ML inverter if the number of cascaded cells is lower than seven, or adjusting firing angles is better. After detailed analysis, it points out that the Ⅱ-type can realize power balance by adjusting firing angles in one output cycle, whereas the Ⅲ-type cascaded multilevel inverter can not ensure power balance. Since the switching mode is redundant for the Ⅱ-type, it has several kinds of power balance equations. Finally, a one phase 2kVA prototype is designed to verify the validity of the power balance strategy for Ⅱ-type.

关 键 词：级联多电平逆变器 阶梯波 功率均衡 

分 类 号：TM46[电气工程—电器]