I型三电平PCS中点电位平衡控制技术  

Neutral Point Voltage Balance Control of Type-I Three-Level PCS

作　　者：张霄杰 毛行奎[1] 郑嘉冬 张哲 董纪清[1] ZHANG Xiaojie;MAO Xingkui;ZHENG Jiadong;ZHANG Zhe;DONG Jiqing(College of Electrical Engineering and Automation,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]福州大学电气工程与自动化学院,福建福州350108

出　　处：《电器与能效管理技术》2023年第9期18-23,共6页Electrical & Energy Management Technology

基　　金：国家自然科学基金项目(51207025、52107183)。

摘　　要：针对I型三电平储能变流器(PCS)固有存在的中点电位不平衡问题,基于空间矢量调制方式分析了中点电位不平衡原理,提出结合七段式和五段式的混合调制策略。在中点电位偏移较大时,采用带可变平衡因子的七段式空间矢量脉宽调制(SVPWM),迅速调节中点电位;在中点电位偏移较小时,采用大电流不开关五段式SVPWM,有效减少开关管开关次数,降低损耗。搭建1台12 kW PCS样机,实验结果表明,所提混合调制策略相较于传统七段式调制策略,中点电位偏移以及波动降低,且样机效率提升了约0.3%。同时,验证了所提混合调制策略的正确性和有效性。In response to the inherent neutral point voltage imbalance problem in type-I three-level power conversion system(PCS),the principle of neutral point voltage imbalance is analyzed based on space vector modulation,and a hybrid modulation strategy is proposed combining seven segment space vector pulse width modulation(SVPWM)with five segment SVPWM.When the neutral point voltage offset is large,the seven segment SVPWM with balance factor is used to quickly adjust the neutral point voltage.When the neutral point voltage offset is small,the five segment SVPWM without switching at high current is adopted to effectively reduce the switching times of the switch and reduce the loss.A 12 kW PCS prototype is built.The experiments show that compared with the traditional seven segment SVPWM,the neutral point voltage offset and fluctuation of the hybrid modulation strategy is reduced,and the efficiency of the prototype is improved by about 0.3%.The correctness and effectiveness of the proposed hybrid modulation strategy are verified.

关 键 词：三电平储能变流器 中点电位不平衡 空间矢量调制方式 混合调制策略 

分 类 号：TM910.1[电气工程—电力电子与电力传动]