As a key component of gas-insulated metal-enclosed switchgear (GIS)

the surface electrical withstand performance of basin insulator is the key factor to determine the insulation margin of GIS equipment. In order to improve the surface electrical withstand performance of basin insulators

we proposed a preparation method of conductivity-tempera- ture adaptive composite coating for improving the surface electric field distribution. Meanwhile

we analyzed the comprehensive performance of the coating under different filling ratios and the improved coating method

and studied the surface temperature distribution characteristics and surface electrical withstand performance of the research samples before and after they were coated with conductivity-temperature adaptive composite coating. The results show that the surface temperature of the insulator sample decreases gradually from the guide rod to the grounding flange

and the surface temperature difference of the sample coated with the conductivity-temperature adaptive composite material is less than 10% compared with that of the uncoated sample. When the content of TiO2 is 30%~50%

the comprehensive properties of the composites are better. Under the coupled electro-thermal field

the surface flashover voltage of basin insulator decreases gradually with the increase of surface temperature gradient. The conductivity-temperature adaptive composite materials with different components and different segments can improve the surface flashover voltage of the insulator. When the temperature of the guide rod is 40~80 ℃

the surface flashover voltage of the test sample coated with a 50% TiO2 filling composite material is increased by 17.74%~15.22% compared with that of the uncoated sample. The research results provide a reference for improving the surface electrical withstand performance of AC basin insulators.