Development and test of epoxy composite for vacuum insulator

A new kind of epoxy composite for vacuum insulator of the pulsed power devices is developed. The preparation process and the test result of the composite sample are presented in this paper. Some samples with different weight percentage are developed for the test. From the result, we can get that loading a quantity of hydrated alumina powder into the epoxy can decrease the surface resistivity from 5 × 10¹⁶ Ω to 6 × 10¹¹ Ω. And using this method favors releasing the residual charge that deposited in the insulator surface during flashover. As a result, the flashover voltage of the epoxy composite is increased from 17 kV to 28 kV at same experiment condition.