Research on Multi Field Coupled Simulation Method of Gas-insulated Switchgear

Abstract Given the increasing use of gas-insulated switchgear (GIS) in high-voltage power systems, accurate prediction of internal temperature distribution is crucial for maintaining operational reliability and preventing failures caused by overheating. Traditional simulation methods, which only consider separate heat transfer or fluid dynamics, are inadequate for describing the complex interactions within GIS. This study introduces a comprehensive multi-physical field coupling approach using COMSOL to model the electric-magnetic-thermal-fluid dynamics in a 252 kV three-phase GIS. The method first performs electromagnetic field simulations, calculating eddy current and ohmic losses by considering skin and proximity effects. These losses are then used as heat sources in a coupled thermal-fluid model to analyze the temperature distribution, taking into account heat conduction, convection, and radiation within the SF6 gas-insulated environment. The results reveal that temperature distribution is symmetric, with the highest temperature observed near the conductor and lower temperatures near the enclosure. These findings provide critical insights for optimizing the design and cooling mechanisms of GIS equipment, aiding in fault prediction and enhancing the overall stability of power systems under various operating conditions.