Design of GIS insulation structure equivalent electric field model for partial discharge simulation

This article develops an equivalent model capable of simulating the electric field of an actual GIS basin insulator. By deconstructing a system comprising a spherical high-voltage conductor and an infinitely large charged flat plate, it is verified that the electric field modulus on a specified radial extension segment of the spherical high-voltage conductor exhibits high similarity to the external radial electric field modulus of an infinitely long high-voltage cylindrical conductor. Subsequently, simulation analysis was conducted on the external surface electric field strength of the actual basin insulator, establishing the relationship between the electric field strength magnitude and position. Finally, an equivalent electric field model was constructed, and the L-BFGS algorithm was employed to quantitatively analyze the similarity between the equivalent model and the electric field of the actual basin insulator. By adjusting the parameters of the equivalent model, the version with the highest degree of fit to the electric field of the actual basin insulator was identified. The established equivalent electric field model shares the same insulation interface structure as the actual GIS basin insulator, with a highly similar background electric field. It can be effectively applied in laboratory partial discharge experiments, and the experimental results provide valuable insights for studying partial discharge in actual GIS basin insulators.