Abstract: This article provides a detailed introduction to the design features of the new 126 kV three-phase common enclosure basin insulator and uses finite element analysis software to perform detailed calculations and analysis of its insulation and mechanical performance.The research results show that by increasing the grounded shielding ring,the electric field intensity in the three-phase junction area can be effectively reduced.The design structure of the basin insulator with a circular convex platform can withstand high gas pressure values.During the casting process,applying a special material surfactant agent on the surface of the central component can effectively improve the bonding strength of the component.The insulator passed successfully a complete set of type tests,further confirming its high insulation performance and mechanical reliability.

Key words: basin insulator, insulation performance, mechanical performance, grounding shield ring, finite element method, surfactant