RVVB护套线过电流诱发短路故障发生概率与起火燃烧过程分析  

Analysis on occurrence probability of short circuit fault induced by over current of RVVB sheathed wire and its ignition and combustion process

作　　者：孙烨 李阳 王朴真 杨雯 林庆文 SUN Ye;LI Yang;WANG Puzhen;YANG Wen;LIN Qingwen(Squad Two of Graduate Faculty,China People’s Police University,Langfang Hebei 065000,China;Physical Evidence Appraisal Center,China People’s Police University,Langfang Hebei 065000,China;College of Safety Science and Engineering,Xi’an University of Science and Technology,Xi’an Shaanxi 710054,China)

机构地区：[1]中国人民警察大学研究生二队,河北廊坊065000 [2]中国人民警察大学物证鉴定中心,河北廊坊065000 [3]西安科技大学安全科学与工程学院,陕西西安710054

出　　处：《中国安全生产科学技术》2021年第3期137-142,共6页Journal of Safety Science and Technology

基　　金：国家自然科学基金项目(52074213);中国人民警察大学校级科研重点专项项目(2019sycxpd001)。

摘　　要：为深入研究电气火灾中护套线因过电流诱发短路故障的转化过程,搭建RVVB护套线过电流诱发短路故障电路,统计短路发生概率,借助高速影像,获取短路发生的时间和次数,分析护套线起火燃烧过程。结果表明:在过电流故障发生1 h内,I≤16 A时护套线仅线芯发热、绝缘炭化,无法诱发短路;I=24 A时护套线发生短路概率为40%,在973 s内发生初次短路;32 A≤I<48 A时护套线发生多次短路的概率随电流值增大而增大,在I=48 A时达到50%,发生初次短路的时间随电流值增大而减小,最短时间为28 s;短路引发绝缘层燃烧的概率随电流值增大呈指数递增,I=24 A时护套线在短路后发生燃烧的概率为62.5%,在48 A时达到100%,短路后1618 ms内火焰可蔓延至护套线两端,形成全线燃烧现象。研究结果可对溯源电气火灾发生的根本原因提供数据支撑。In order to study the transformation process of short circuit fault caused by over current of sheathed wire in the electrical fire,the short circuit fault circuit induced by over current of RVVB sheathed wire was built,and the probability of short circuit occurrence was counted.With the help of high-speed camera,the time and number of short circuit were obtained,and the ignition and combustion process of sheathed wire were analyzed.The results showed that within 1 hour of the occurrence of over current fault,when I≤16 A,the core of sheathed wire was only heated and the insulation was carbonized,which could not induce short circuit.When I=24 A,the short circuit probability of sheathed wire was 40%,and the first short circuit occurred within 973 s.When 32 A≤I<48 A,the probability of multiple short circuit of sheathed wire increased with the increased of current,and reached 50%when I=48 A,the time of the first short circuit decreased with the increased of current,and the shortest time was 28 s.The probability of insulation layer combustion caused by short circuit increased exponentially with the increased of current,and the probability of sheathed wire combustion after short circuit was 62.5%when I=24 A,and it reached 100%when I=48 A.The flame could spread to both ends of sheathed wire within 1618 ms after short circuit,then the whole line combustion phenomenon formed.The research results can provide data support for tracing the root causes of electrical fire.

关 键 词：电气火灾 RVVB护套线 过电流 短路故障 起火燃烧 

分 类 号：X928.7[环境科学与工程—安全科学]