计及金属化薄膜电容器与IGBT模块退化过程相关性的柔直换流阀组件可靠性评估方法  

Reliability Evaluation Method for VSC-HVDC Valve Submodules Considering the Correlation between the Degradation Process of Metallized Polypropylene Film Capacitors and IGBT Modules

作　　者：张午宇 齐磊 张翔宇 崔翔 郭宁明 Zhang Wuyu;Qi Lei;Zhang Xiangyu;Cui Xiang;Guo Ningming(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing 100096,China;China Electric Power Planning&Engineering Institute Co.Ltd Beijing 100120,China;C-EPRI Electric Power Engineering Co.Ltd Beijing 102200,China)

机构地区：[1]新能源电力系统全国重点实验室(华北电力大学),北京100096 [2]电力规划总院有限公司,北京100120 [3]中电普瑞电力工程有限公司,北京102200

出　　处：《电工技术学报》2024年第14期4508-4518,共11页Transactions of China Electrotechnical Society

基　　金：国家电网有限公司科技资助项目(5500-202140126A-0-0-00)。

摘　　要：基于模块化多电平拓扑的换流阀是柔性直流输电系统的核心装备,随着柔直换流阀运行电压、功率密度以及运行场景的不断拓展,其运行可靠性成为突出问题。现有的柔直换流阀可靠性评估方法忽略了金属化薄膜电容器与IGBT模块性能退化的耦合关系,致使评估结果不准确。为此,该文提出了计及金属化薄膜电容器与IGBT模块退化过程相关性的可靠性评估方法。IGBT模块寿命采用威布尔分布,考虑了换流阀运行过程中的任务剖面变化;基于Wiener过程对金属化薄膜电容器的可靠性进行了评估,利用Copula理论将容值退化程度与IGBT模块寿命之间的耦合关系进行了建模。所提可靠性评估方法修正了现有不考虑相关性方法对柔直换流阀可靠性评估结果,平均无故障时间从4.05年修正为5.20年,评估结果更加精确。Flexible DC transmission technology can rapidly and flexibly control active and reactive power in large-scale new energy power transmission,providing voltage support to weak AC or passive systems.With the increasing demand for system capacity and the expansion of engineering application scenarios,it is of great engineering significance to accurately and real-time evaluate the operational reliability of flexible and direct converter valves as core equipment.However,most existing reliability assessment methods focus on modeling the reliability of key components such as IGBT modules and metalized thin film capacitors,neglecting the coupling relationship between component degradation processes.Previous studies have shown that capacitor capacity degradation causes an increase in IGBT module switching frequency,affecting the reliability of IGBT modules.Therefore,this paper proposes a reliability evaluation method for flexible direct converter valves,considering the correlation between the degradation process of capacitors and IGBT modules.Copula theory is used to model the coupling relationship between capacity degradation and IGBT module life,improving the accuracy of reliability evaluation results for flexible direct converter valves.The reliability evaluation of IGBT modules considers the influence of typical mission profiles of flexible and direct converter valves,and the life distribution adopts the Weibull distribution model.The IGBT module losses include static and dynamic losses.Static losses include IGBT on-state losses,IGBT off-state losses,diode on-state losses,and diode off-state losses.Athermal network model is established using the principle of electrical analogy,which includes heat sinks,ambient temperature,and device packaging structure.The junction temperature of the IGBT is calculated.The variable amplitude load is converted into a complete cycle of a series of transverse thermal loads using statistical notation.According to the linear damage principle,the cumulative life loss of IGBT is calculated.De

关 键 词：柔性直流换流阀 可靠性评估 金属化薄膜电容器 IGBT模块 COPULA理论 

分 类 号：TM464[电气工程—电器]