Research on the temperature and flow velocity characteristic of GIL based on multi-field coupling

With the development of technology of Gas-insulated Metal Enclosed Transmission Line (GIL), GIL is used all over the world gradually. Compared with the existing overhead lines and cables, Gas-insulated Metal Enclosed Transmission Line has many significant advantages. As it has a wide voltage range and various installation methods, it is widely used in power system and transmission field. In recent years, there have been many accidents of GIL caused by overheat faults in the world. Therefore, the safe and reliable operation of GIL is of great significance. In this paper, a multi-physics model of UHV GIL transmission pipeline is constructed. Through temperature field simulation, the temperature distribution of disc insulator and flow velocity field distribution of gas-solid interface in GIL pipeline is studied. Additionally, contact resistance of inserted-connected structure of GIL has been taken into account. Temperature distribution of GIL can be obtained. When the contact resistance is prone to deteriorate, the high temperature area is transferred from the conductor to the plug structure.