环网柜熔断器垂直和水平布置下温度分布特性

环网柜内的熔断器因长时间工作在大电流环境下,其散热能力对于维持自身正常工作性能至关重要。实际运行经验表明,环网柜内熔断器垂直和水平布置时其故障率存在差异。为此研究了在自然对流条件下,环网柜内熔断器垂直和水平布置时的散热过程及差异。首先基于多物理场耦合软件COMSOL,建立了自然对流条件下的环网柜内熔断器流场和温度场直接耦合的三维仿真模型,对两种布置方式下熔断器的流场和温度场进行了仿真计算;并利用温度分布试验平台测量熔断器关键部位的温度,与仿真结果进行对比与验证。研究结果表明,在正常工作电流下,熔断器垂直布置时最高和最低温度较水平布置分别高13.38%和13.30%;垂直布置熔断器的温度分布呈明显的两端不对称性;水平布置熔断器的温度分布呈两端对称性。研究结果能够为熔断器热故障分析及环网柜熔断器的优化布置提供一定参考。

Study on Temperature Distribution Characteristics in Vertical and Horizontal Arrangement of Ring Network Cabinet Fuse

Because of the long time working in the high current environment, the heat dissipation capacity of fuses in the ring cabinet is very important for maintaining its normal working performance. The actual operation experience shows that the failure rate of fuses in vertical and horizontal arrangement is different. For this purpose, the heat dissipation process and the difference between the vertical and horizontal fuses in the ring cabinet are studied under natural convection conditions. First, based on the multi physical field coupling software COMSOL, a three-dimensional simulation model of the direct coupling of the flow field and the temperature field in a ring network cabinet under the condition of natural convection is established. The flow field and temperature field of the fuse are simulated with two vertical and horizontal arrangements, and the temperature distribution test platform is used to measure the fuse. The temperature of the key part is compared with the simulation results. The results show that under the normal working current, and the maximum and minimum temperature of the fuse is 13.38% and 13.30% higher than the horizontal arrangement respectively, vertical fuse temperature distribution is of obvious asymmetry at both ends, the temperature distribution of a horizontal symmetry at both ends of the fuse. The research results can provide some references for the thermal fault analysis of the fuse and the optimal layout of the fuse box of the ring net..