The high voltage insulation equipment on the roof of high-speed train is exposed to the high-speed airflow environment while the high-speed train is running. Thus its external insulation characteristics are significantly different from those without airflow. In this paper

according to the flashover characteristics and discharge path deviation phenomenon of roof insulators in airflow environment

two kinds of aerodynamic structure optimization schemes of roof insulators were proposed

and the test models of roof insulators were fabricated by 3 D printing technology. Finally

the finite element analysis software was used to analyze the surrounding airflow conditions and the electric field distribution of the aerodynamic roof insulator

and the tests for flashover characteristics under the airflow environment were carried out through the wind tunnel test system. The results show that the maximum and average values of the surface field strength of the two aerodynamic insulators are lower compared to those of traditional structural insulator; under the condition of wind speed of 100 m/s

their flashover voltages increase by 11.3% and 8.5%

respectively

and the existence of airflow affects the motion mode of electrons

ions and metastable particles in the electric field

affecting the discharge formation process. The optimized roof insulator exhibits better aerodynamic characteristics

and its external insulation performance in the airflow environment is improved compared to the traditional structure.