Scale Modeling on the Overheat Failure of Bus Contacts in Gas-Insulated Switchgears

This paper deals with the scale modeling method to investigate the overheat failure mechanism and the processes of bus contacts in gas-insulated switchgears (GIS). Mathematical models of the physical phenomenon in the overheat failure process are summarized to derive the coupled eddy current-fluid-heat field scaling relationships. In pursuit of better availability of the model, the scaling relationships are then simplified and a partial scale model is further designed with the dimension parameters, physical parameters, and boundary conditions presented. Temperature distributions and current densities of the scale model are compared with those of the prototype to verify the effectiveness of the scale model by 3-D finite-element method. The test scale model is fabricated, and the temperature rise tests are conducted to validate the correctness of the scale modeling and the simulation calculation.