高压电缆缓冲层烧蚀至绝缘屏蔽层的电流密度临界条件仿真研究  

Simulation study on critical condition of current density for ablation of high voltage cable buffer layer to insulating shield layer

作　　者：门业堃 张可[2] 郭卫 及洪泉 任志刚 张竟成[3] 高建 MEN Yekun;ZHANG Ke;GUO Wei;JI Hongquan;REN Zhigang;ZHANG Jingcheng;GAO Jian(Electric Power Research Institute of State Grid Beijing Electric Power Company,Beijing 100075,China;Xi′an Jiaotong University,Xi′an 710049,China;State Grid Beijing Electric Power Company,Beijing 100075,China)

机构地区：[1]国网北京市电力公司电力科学研究院,北京100075 [2]西安交通大学,陕西西安710049 [3]国网北京市电力公司,北京100075

出　　处：《绝缘材料》2025年第3期109-116,共8页Insulating Materials

基　　金：国家电网公司总部科技项目(5108-202218280A-2-353-XG)。

摘　　要：为了研究高压电缆缓冲层烧蚀的临界条件,本文针对实际电缆烧蚀致绝缘屏蔽损伤的类型进行分类总结,通过有限元仿真构建三维不对称高压电缆模型,分别研究了干燥和潮湿条件下高压电缆烧蚀发展过程及其对绝缘屏蔽造成损伤的机理,并对比分析两种条件下烧蚀的难易程度。结果表明:干燥条件下绝缘屏蔽层损伤源于电缆长段不良接触导致的电流热效应,不良接触达到7.5 m时缓冲层表面电流密度高达442 A/m^(2),温度为200℃;潮湿条件下绝缘屏蔽层损伤源于电化学腐蚀高阻性产物生成导致的电流热效应,高阻性产物在电流密度与温度集中的区域会贯穿缓冲层,被白色粉末覆盖比例达到97.9%时缓冲层表面电流密度高达416 A/m^(2)。仿真结果能够与实际烧蚀故障电缆的解体情况对应良好,验证了本文分析结果的合理性。To investigate the critical conditions of high voltage cable buffer layer ablation,the types of insulation shielding damage caused by actual cable ablation were summarized in this paper.A three-dimensional asymmetric high-voltage cable model was established by finite element simulation.The ablation development process of high-voltage cables under both dry and wet conditions,as well as the mechanisms of their damage to insulation shielding,were studied separately.The difficulty of ablation under the two conditions was compared and analyzed.The results show that damage under dry condition is attributed to current-induced thermal effects caused by prolonged poor contact.When poor contact extends to 7.5 m,the surface current density on the buffer layer reaches as high as 442 A/m^(2),and the temperature reaches high as 200℃within the buffer layer.Damage under wet condition arises from current-induced thermal effects caused by the high resistance products from electrochemical corrosion,and these products can penetrate areas where current and temperature are concentrated within the buffer layer.When the coverage rate of white powder reaches 97.9%,the surface current density on the buffer layer is up to 416 A/m^(2).Simulation results align closely with actual dissolution observed in faulty cables affected by ablation,thus validating our analysis findings presented in this paper.

关 键 词：缓冲层烧蚀 绝缘屏蔽层 电流热效应 电化学腐蚀 有限元仿真 

分 类 号：TM215[一般工业技术—材料科学与工程] TM247[电气工程—电工理论与新技术]