摘要
三电平Buck-Boost变流器具有双向馈能和能量传输高效的特点。针对直流电容器容值衰退和IGBT开路故障两种典型失效模式,提出了一种利用变流器自身传感器同时对直流电容容值衰退和IGBT开路故障非侵入式在线监测的方法。首先,分析了三电平Buck-Boost变流器开关运行模态及其切换顺序。然后,采用特定开关模态消除直流电容等效串联电阻(equivalent series resistance,ESR)影响,分别推导了子模块电容的容值特征解析表达式。最后,利用每个开关周期计算出的等效容值特征检测和定位IGBT开路故障。仿真和实验结果表明:利用开关模态容值特征能够同时监测三电平Buck-Boost变流器直流电容状态和IGBT开路故障,平均容值监测误差小于1%且可以消除ESR的影响,利用容值特征畸变能够在2~3个开关周期内检测出IGBT开路故障。
Three-level Buck-Boost converter possesses characteristics of bidirectional energy feeding and high-efficient energy conversion.The DC-link capacitor capacitance degradation and IGBT open-circuit failure are the two typical failure modes for the three-level Buck-Boost converters.This paper proposes a non-intrusive online monitoring method of DC-link capacitor capacitance degradation and IGBT open-circuit faults simultaneously by using the existing sensors in converter.First,the switching operation modes and switching sequences of the three-level Buck-Boost converter are analyzed.Then,the effect of equivalent series resistance(ESR)is eliminated by utilizing specific switching modes,and the analytical expressions of the sub-module DC-link capacitance characteristics are derived.Finally,the equivalent capacitance characteristics calculated from each switching cycle are used to detect and locate the IGBT open-circuit faults.The simulation and experimental results show that switching mode capacitance features can be used to simultaneously monitor the health state of DC-link capacitor and the IGBT open-circuit fault for the three-level Buck-Boost converter.Specifically,the average capacitance monitoring error of the DC-link capacitor is less than 1%and the effects of ESR can be eliminated.The IGBT open-circuit fault can be detected within 2~3 switching cycles from the distortion of switching mode capacitance features.
作者
崔勇
李豪
向大为
岳朋朋
杨兴武
CUI Yong;LI Hao;XIANG Dawei;YUE Pengpeng;YANG Xingwu(College of Electrical Power Engineering,Shanghai University of Electric Power,Shanghai 200090,China;College of Electronics and Information Engineering,Tongji University,Shanghai 201804,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2023年第10期4345-4354,共10页
High Voltage Engineering
基金
国家自然科学基金(51907116)
上海市自然科学基金(22ZR1425400)。
