主管：中华人民共和国应急管理部
主办：应急管理部天津消防研究所
ISSN 1009-0029  CN 12-1311/TU
消防科学与技术

消防科学与技术 ›› 2025, Vol. 44 ›› Issue (11): 1637-1643.

• • 上一篇    下一篇

火灾短时高温下电缆绝缘材料劣化特性模拟研究

蔡静1, 郭卫1, 李华春2, 及洪泉1, 任志刚1   

  1. （1.国网北京市电力公司电力科学研究院，北京100075； 2.国网北京市电力公司，北京 100031）
  • 收稿日期:2024-08-16 修回日期:2024-10-07 出版日期:2025-11-20 发布日期:2025-11-15
  • 作者简介:蔡 静，国网北京市电力公司电力科学研究院工程师，主要从事高压电缆设备技术方面的研究，北京市丰台区南三环中路30号，100075，1798559711@qq.com。
  • 基金资助:
    国网北京市电力公司科技项目（520223230013）

Simulation on the degradation characteristics of cable insulation materials under temporary high temperature of fire

Cai Jing1, Guo Wei1, LiHuachun2, Ji Hongquan1, Ren Zhigang1   

  1. (1. State Grid Beijing Electric Power Research Institute,Beijing 100075,China; 2. State Grid Beijing Electric Power Company, Beijing 100031, China)
  • Received:2024-08-16 Revised:2024-10-07 Online:2025-11-20 Published:2025-11-15

摘要： 隧道发生火灾时，火源邻近高压电缆短时处于高温环境中。为研究电缆绝缘材料交联聚乙烯（XLPE）在火灾高温后的劣化特性，本文首先建立仿真模型，分析典型火灾工况下电缆绝缘层的温度变化曲线；然后搭建热处理平台，分别按最高温度300、325、350 ℃的等效温升曲线对XLPE试样进行处理；最后进行微观形貌、官能团、结晶度以及击穿场强测试。试验结果表明：随着劣化温度增加，试样表面的规整性逐渐降低，XLPE分子断裂产生的聚合物碎片和小分子物质聚集在一起，形成颗粒状结构。试样的结晶度由28.67%降低至16.47%；羰基指数由0.022增加至0.344，羟基指数由0.066增加至0.211；击穿场强由74.16 kV/mm下降至50.38 kV/mm。研究结果可为火灾后电缆绝缘的劣化评估和维护更换等提供理论依据。

关键词: 电缆火灾, 短时高温, 绝缘劣化, 微观特性, 击穿场强

Abstract: When a tunnel fire occurs, the high-voltage cables near the fire source are temporarily exposed to high temperatures. The degradation characteristics of cross-linked polyethylene (XLPE) cable insulation material after high temperature of fire need to be studied. Firstly, a simulation model is established to analyze the temperature variation curve of the cable insulation layer under typical fire conditions in this paper. Then the heat treatment platform is built. XLPE samples are processed according to the equivalent temperature rise curves with the highest temperatures of 300, 325, 350 ℃. Finally, the microstructure, functional groups, crystallinity, and breakdown field strength of the sample are tested. The results indicate that as the degradation temperature increases, the regularity of the sample surface gradually decreases. The polymer fragments and small molecular substances generated by XLPE molecule breakage aggregate together to form a granular structure. The crystallinity decreased from 28.67% to 16.47%. The carbonyl index increased from 0.022 to 0.344, and the hydroxyl index increased from 0.066 to 0.211. The breakdown field strength decreased from 74.16 kV/mm to 50.38 kV/mm. The research results can provide theoretical basis for the degradation assessment and maintenance replacement of cable insulation after fire accidents.

Key words: cable fire, insulation degradation, microscopic characteristics, breakdown field strength