基于耦合场计算的击穿电弧对电缆温度及应力影响研究

Study on Influence of Insulation Breakdown Arc on Thermal-stress Characteristics of Cable Joints Based on Coupled Field Calculation

电缆绝缘击穿常发生在电缆接头处,击穿电弧对电缆会造成严重的温升和形变,严重威胁电力安全。文章针对电弧发生时的复杂物理过程,提出顺序耦合的计算方法,研究电缆接头复杂的温度场和应力场分布。研究表明电弧损耗受电弧电流大小影响呈非线性指数关系,电弧区域温度和应力呈现波浪型增长。相对电缆表面,电缆内部绝缘受电弧的应力冲击较为严重。研究成果不仅能有效评估电缆内部缺陷及其发展过程,还为研究电缆绝缘材料受电弧击穿的老化特性提供科学依据和理论基础,具有重要的科学和工程意义。

Cable insulation breakdown often occurs at cable joints.Breaking arc often causes severe temperature rise and deformation,which is a serious threat to power safety.In this paper,a sequentialcoupling calculation method is proposed for the complex physical process of arc generation,and the complex temperature field and stress field distribution of cable joints are studied.The study shows that the arc loss is nonlinearly exponentially affected by the arc current,and the arc region temperature and stress show a wave-like growth.However,the internal insulation of the cable is more severe affected by the stress of the arc than that of surface.The research results can not only effectively evaluate the internal defects of the cable and its development process,but also provide a scientific and theoretical basis for studying the aging characteristics of the cable insulation material subjected to arc breakdown.It has important scientific and engineering significance.