|
|
|
| Analysis and countermeasures of a 220 kV voltage transformer fault |
| PENG Kai |
| State Grid Jibei Electric Power Co., Ltd. Ultra-High Voltage Branch, Beijing 102488 |
|
|
|
|
Abstract This paper investigates a secondary voltage anomaly fault in a 220 kV capacitive voltage transformer (CVT). Through comprehensive analysis of test data and post-disassembly internal inspections, the root cause is identified as moisture ingress into the electromagnetic unit, which degrades insulation performance and ultimately leads to insulation breakdown under sustained electric field stress. Notably, the defect is deeply embedded within the electromagnetic unit, evading detection by conventional preventive testing protocols such as dielectric dissipation factor measurements. This case study proposes structural improvements for manufacturers, including enhanced hermeticity design of electromagnetic units to mitigate moisture penetration risks. Furthermore, it offers actionable insights for grid operators to refine condition assessment frameworks and diagnostic strategies, thereby improving the operational reliability of mission-critical metering devices in power systems. Ensuring the operational reliability performance of capacitive voltage transformer carries significant engineering value.
|
|
Received: 20 February 2025
|
|
|
|
[1] 韩慕尧, 罗皓文, 刘傲洋, 等. 一起110kV电容式电压互感器二次零序电压异常波动故障分析[J]. 电气技术, 2021, 22(12): 53-56. [2] 王志全. 110kV电容式电压互感器故障原因检查分析[J]. 高电压技术, 2005, 31(12): 80-81. [3] 魏斌, 蒲军. 顺北油田二区变电站35kV电压互感器烧毁故障分析[J]. 电气技术, 2024, 25(2): 74-78. [4] 王祺元, 靳巩磊, 康婧婧, 等. 高压直流输电工程换流变进线电压互感器断线故障分析[J]. 电气技术, 2023, 24(5): 71-75. [5] 孙美玲, 孙文杰, 梁晖, 等. 110 kV电容式电压互感器试验数据异常升高故障分析[J]. 电工技术, 2024(24): 193-195. [6] 赵彦林, 周志新, 何亮, 等. 一起电容式电压互感器二次电压异常故障分析[J]. 电力电容器与无功补偿, 2025, 46(1): 114-120. [7] 温伟杰, 胡铁伟, 陈晓龙, 等. 典型配电故障下直流偏置电压形成及电压互感器熔断分析[J]. 电工技术学报, 2025, 40(1): 226-240. [8] 叶小佳, 李鹏, 陈前. 一起电容式电压互感器二次电压异常的分析与处理[J]. 电子元器件与信息技术, 2024, 8(11): 273-275. [9] 李威, 胡润阁, 刘亚林, 等. 500 kV CVT电压异常分析与处理[J]. 电力电容器与无功补偿, 2021, 42(3): 74-78. [10] 陈莉, 张瑞明, 宋莉莉. 一起35kV电容式电压互感器二次电压异常分析[J]. 电气技术, 2021, 22(2): 59-62. [11] 杨鸣, 朱豪帅, 邹滨阳, 等. 基于电压互感器的宽频电压测量方法研究综述[J]. 电工技术学报, 2025, 40(7): 2247-2266. |
|
|
|