Abstract：Load current, ambient temperature, contact resistance is an important factor affecting the temperature of high current switchgear. In this paper, the electromagnetic-heat transfer-convection multi-physics coupled simulation model is established by COMSOL to calculate the internal temperature distribution of 4000A high current switchgear. The influence of load current, ambient temperature and contact resistance on the temperature rise of tulip contact and bus bars were studied. The steady state temperature rise experiment of high current switchgear under different load conditions is designed and carried out. The experimental results verify the rationality of the simulation model. The results showed that the temperature rise of tulip contact has exceeded the upper limit at about 80% load current and the forced heat dissipation of switchgear is required. The ambient temperature has a great influence on the temperature rise inside the switchgear. The monitoring of the ambient temperature is necessary in designing the switchgear temperature monitoring system. The increase of contact resistance of contact points has a great influence on the temperature rise of tulip contacts and bus bars. The temperature rise of contacts should be monitored in real time so as to find the abnormal running state. The temperature rise of current transformer in high current switchgear is an important index needed to be considered in the temperature monitor system. The improper installation of current transformer leads to a severe temperature rise of bus bars. The results may provide a theoretical basis for the follow-up to determine the fault location of on-line switchgear temperature monitoring and the design of operation and maintenance plan.
李江涛, 孙义, 李擎宇, 董宁, 赵政. 大电流开关柜温度分布特性的影响因素分析[J]. 电气技术, 2018, 19(9): 12-18.
Li Jiangtao, Sun Yi, Li Qingyu, Dong Ning, Zhao Zheng. Analysis of influencing factors on temperature distribution characteristics of high current switchgear. Electrical Engineering, 2018, 19(9): 12-18.
2018, Vol. 19 
