This study aims to provide a theoretical basis for the fatigue characteristics and structural optimisation of insulating rods to enhance their reliability and lifespan in practical applications. This paper uses COMSOL to complete the stress analysis of insulating rods under dynamic and static loads based on the finite element method. The correctness of the model is verified based on the elastic-plastic theory. The simulation results show that under the same load

the stress concentration area is more affected by the dynamic load

and the stress concentration position is highly consistent with the fracture position of the rod in the experiment. It verifies the impact on the insulating rods at different speeds and static load stress. Simulation shows that

in cases where the allowable stress is exceeded

as the number of operations increases

the fatigue characteristics will greatly affect the service life of the insulation rod. Finally

the fatigue analysis and structural optimisation of the insulating rod were completed

providing important reference values for the long-term stable operation of ultra-high voltage circuit breakers.