摘要
干式空心电抗器采用玻璃纤维增强环氧树脂作为包封绝缘材料,受设备运行过程中的热效应影响,包封材料绝缘性能和力学性能的下降将导致电抗器匝间击穿,严重时会引起局部过热甚至设备烧毁。本文将绝缘电阻和拉伸强度作为失效准则,开展了热老化作用下干式空心电抗器包封材料的失效预测研究。利用高温试验箱对干式空心电抗器包封材料进行老化试验,通过测量绝缘电阻和拉伸强度,获取不同老化时长下包封材料的退化数据。采用Frank Copula函数描述绝缘失效与机械失效之间的相关性,采用最大期望(expectation maximization,EM)算法对模型参数进行估计,在此基础上建立了包封材料二元非线性Wiener失效预测模型,通过与失效试验结果对比验证预测模型的有效性,并基于建立的失效预测模型研究不同温度下包封材料的寿命分布特性。结果表明:包封材料的寿命随着温度升高呈指数规律下降,110℃下包封材料的平均寿命为19.6年,130℃下包封材料的平均寿命为3.2年,160℃下包封材料的平均寿命为0.12年。
The encapsulate material of dry-type air-core reactor is glass fiber reinforced epoxy resin,affected by thermal effect during equipment operation, the insulating and mechanical properties of encapsulate material decrease, which will lead to inter-turn breakdown of reactor and local overheating even equipment burnout in severe case. In this paper, taking insulation resistance and tensile strength as failure criteria, failure prediction of encapsulate material for dry-type air-core reactor under thermal ageing process were studied. Ageing experiments were conducted on the encapsulate material in high-temperature test chamber, and the degradation data of encapsulate material under various ageing time were obtained by measuring the insulation resistance and tensile strength. The relationship between insulation failure and mechanical failure were described by Frank Copula function, and the model parameters were estimated by Expectation Maximization(EM) algorithm. Then failure prediction model of encapsulate material was built based on binary nonlinear Wiener process, and its effectiveness was verified by failure experiments.The prediction model was used to study the lifetime distribution characteristics of encapsulate material under different operation temperature. The results show that the lifetime of encapsulate material decreases exponentially with the increase of operation temperatures, and the average lifetime of encapsulate material at 110 ℃, 130 ℃, and 160 ℃ is 19.6 years, 3.2 years, and 0.12 year, respectively.
作者
董哲
刘孔瑞
彭辉
DONG Zhe;LIU Kongrui;PENG Hui(School of Electrical Engineering and Automation,Wuhan University,Wuhan 430072,China;State Grid Nanchang Power Supply Company,Nanchang 221008,China)
出处
《绝缘材料》
CAS
北大核心
2020年第5期101-106,共6页
Insulating Materials
关键词
干式空心电抗器
包封材料
热老化
WIENER过程
失效预测
dry-type air-core reactor
encapsulate material
thermal ageing
Wiener process
failure prediction
