The Spatiotemporal Distribution of Temperature and Electromagnetic Force in Low-Voltage Electrical Penetrations Under Short-Circuit

Electrical penetrations are crucial for the safe and stable operation of nuclear power plant reactors, serving as power supply, dynamic monitoring of the reactors, resistance to nuclear leak and so on. As a result, it is important to investigate the performance of electrical penetrations in extreme circumstances such as short-conditions. In this work, a three-dimensional electromagnetic-thermal coupled model for low-voltage electrical penetration components with connecting cables is established, in which spatial and temporal distribution characteristics of temperature and electromagnetic force are calculated utilizing finite element method. The results indicated that electrical penetration components experienced a significant temperature rise under short-circuit conditions, especially the thin layer of poly(ether-ether-ketone) (PEEK) next to conductor where temperature was elevated from 20 to 390°C in one second. Besides, the temperature of PEEK increased with short-circuit time linearly approximately. In addition, electromagnetic force between conductor components increased quadratically with the short-circuit current. It was demonstrated that the distribution of temperature and electromagnetic force were influenced tremendously by the arrangement of conductors. This work may contribute to the structural optimization of electrical penetrations in engineering applications.