【摘要】 通过对熔断器熔体在8/20μs雷电流作用下温升过程数学模型的推导及分析，认为熔体材料热传导系数、常温电阻率、环境温度及熔体异常断裂均有可能影响熔体温升过程，进而影响熔断器工作性能。在对某熔断器熔体结构进行合理简化，并针对实际情况提出相关假设的基础上，利用Ansys有限元软件建立熔体热电耦合有限元模型，对正常熔体及受上述4种因素影响熔体在不同雷电流幅值作用下温升情况进行了仿真，得到了不同情况下熔断器的雷电流幅值-弧前时间特性曲线。由仿真结果可知，这4种影响因素均会影响雷电流作用下熔体温升速度，进而影响熔体温升过程，从而改变熔断器在雷电流幅值作用下的弧前时间，可能造成熔断器发生熔断，导致熔断器工作性能下降。最后通过对仿真结果的分析比较，提出4种保障熔断器安全正常运行的措施。更多还原

【Abstract】 Through derivation and analysis on mathematical model of the temperature rise process of fuse melt under 8/20 μs lightning current, it is considered that the thermal conductivity of melt material, the normal temperature resistivity, the ambient temperature and the abnormal fracture of melt may affect the temperature rise process of fuse melt and then affect its working performance. On the basis of reasonably simplifying the melt structure of a fuse and putting forward relevant assumptions according to the actual situation, the melt thermoelectric coupling finite element model is established by using ANSYS, and the temperature rise of normal melt and melt affected by the above four factors under different lightning current amplitudes is simulated. The characteristic curves of lightning current amplitude-pre arc time of fuse are obtained. It is shown that these four factors will affect the melt temperature rise speed under the action of lightning current, and then affect the melt temperature rise process and the fuse pre arc time, which may cause the fuse to melt and reduce the working performance. Finally, through the comparison of simulation results, four measures to ensure the safe and normal operation of fuse are put forward.更多还原