金属化膜电容器多频阻抗特征及健康状态评估方法  

Multi-Frequency Impedance Characteristics and Deterioration State Evaluation Method of Metallized Film Capacitors

作　　者：闫昕旖 郑琳子[1] 许馨愉 熊庆 祝令瑜[1] 汲胜昌[1] 徐阳 陈阳 YAN Xinyi;ZHENG Linzi;XU Xinyu;XIONG Qing;ZHU Lingyu;JI Shengchang;XU Yang;CHEN Yang(School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Electric Power Research Institute,State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing 211100,China)

机构地区：[1]西安交通大学电气工程学院,西安710049 [2]国家电网江苏省有限公司电力科学研究院,南京211100

出　　处：《西安交通大学学报》2025年第3期160-171,共12页Journal of Xi'an Jiaotong University

基　　金：国家电网有限公司总部科技项目(5108-202218280A-2-355-XG)。

摘　　要：为评估柔性直流输电系统中金属化膜电容器的运行状态,分析其失效原因,提出了一种利用多频阻抗特征实现金属化膜电容器健康状态评估的方法。首先,建立电容器的串并联等效模型,提取表征金属化膜电容器劣化特性参量;其次,搭建金属化膜电容器加速老化测试平台及多频阻抗测试平台,获取不同劣化状态与劣化原因的电容器样品;最后,提取金属化膜电容器多频阻抗曲线中特征参量α_(S)、α_(P)和转折频率,对不同电容器的特征参量变化进行分析。结果表明,电容器在直流电压作用下劣化时,α_(S)>1.91表征导电部分劣化加剧,α_(P)>0.17及转折频率高于150 Hz表征介质部分劣化加剧。该方法不仅可以识别电容器的劣化程度,还能直观反映电容器的劣化部位及原因,对喷金不良、灌封品质差的电容器具有良好的检出效果。To assess the operational status of metallized film capacitors in flexible DC transmission systems and analyze their failure causes,a method for health assessment of metallized film capacitors using multi-frequency impedance characteristics is proposed.Firstly,an equivalent series-parallel equivalent model of the capacitor is established to extract characteristic parameters representing the degradation of metallized film capacitors.Secondly,a testing platform for accelerated aging of capacitors and a multi-frequency impedance testing platform for metallized film capacitors are set up to obtain capacitor samples in different degradation states due to varying degradation causes.Finally,characteristic parameters α_(S),α_(P) and inflection frequency are extracted from the multi-frequency impedance curve of metallized film capacitors to analyze the changes in characteristic parameters of different capacitors.The results indicate that when capacitors deteriorate under DC voltage,if α_(S)>1.91,it signifies an exacerbation of the conductive part degradation,and if α_(P)>0.17 and the inflection frequency is higher than 150 Hz,it indicates an exacerbation of the dielectric part degradation.This method not only identifies the degree of capacitor degradation but also visually reflects the degraded parts and causes of capacitors,demonstrating good detection performance for capacitors with poor metallization,and inferior sealing quality.

关 键 词：金属化膜电容器 健康状态评估 劣化特性 多频阻抗 

分 类 号：TM536[电气工程—电器] TM930.12