金属化膜电容器电极边缘电场畸变研究  

Research on Electric Field Distortion at the Edge of Metallized Film Capacitor Electrode

作　　者：王佳昕 李化 王哲豪 李柳霞 林福昌 WANG Jiaxin;LI Hua;WANG Zhehao;LI Liuxia;LIN Fuchang(State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学电气与电子工程学院强电磁工程与新技术国家重点实验室,武汉430074

出　　处：《高压电器》2022年第3期29-36,共8页High Voltage Apparatus

基　　金：国家自然科学基金资助项目(51822704)。

摘　　要：金属化膜电容器因其自愈特性可在高电场强度下工作,但电极边缘的电场畸变导致的电极退化会使电容量下降,对电极边缘处的电场畸变程度的评估可为电容器的结构设计提供支撑。文中基于三结合点附近电场分布特点,提出了一种评估电极边缘电场畸变程度的新方法,以T型金属化膜电容器为计算模型,对有限元得到的电极附近电场的数值解,采用电场分布的理论解析式进行拟合,拟合优度在99%以上,定义拟合系数为电场畸变系数来评估电场畸变程度,并得到电极厚度、薄膜厚度和分割间隙对电场畸变程度的影响规律:电场畸变系数随电极厚度的减小呈幂函数形式增大,随薄膜厚度和分割间隙的减小呈幂函数形式减小,同时根据多参数关系式可准确预估电场畸变系数。Metallized film capacitors can work under high electric field strength due to their self⁃healing characteris⁃tics,but the electrode degradation due to electric field distortion at the edge of the electrode will reduce the capaci⁃tance,so the evaluation of the degree of electric field distortion at the edge of the electrode can provide support for the structural design of the capacitor.Based on the characteristics of the electric field distribution near the three⁃combina⁃tion point,a kind of new method to evaluate the degree of electric field distortion at the edge of the electrode is pro⁃posed.The T⁃type metallized film capacitor is used as the calculation model,the numerical solution of the electric field near the electrode,which is obtained by the finite element method,is fitted by the theoretical analytical formu⁃la adopting electrical field distribution and the goodness of fit is above 99%.The fitting coefficient is defined as the electric field distortion coefficient to evaluate the degree of electric field distortion,and the law of the influence of electrode thickness,film thickness and segmentation⁃gap width on the degree of electric field distortion is obtained:the electric field distortion coefficient increases in the form of a power function with the decrease of electrode thick⁃ness,and decreases in the form of a power function with the decrease of the film thickness or segmentation⁃gap width and,at the same time,the electric field distortion coefficient can be accurately estimated in accordance with the multi⁃parameter relationship.

关 键 词：金属化膜电容器 三结合点 电场畸变 

分 类 号：TM53[电气工程—电器]