Effect of UV radiation aging on creepage discharge characteristics of high temperature vulcanized silicon rubber at high altitude

The physicochemical properties and creepage discharge characteristics of aged high temperature Vulcanized (HTV) silicone rubber materials were investigated by ultraviolet radiation (UV) aging method in this study. The experimental results show that as the aging time increases, the creepage discharge flashover voltage increases first and then decreases. But the aging time has little effect on the creepage discharge inception voltage. With the aging time prolonged, the discharge endurance time of HTV silicone rubber is shortened, and the creepage discharge development velocity is accelerated. In the short time of applying voltage to aging material, the magnitude of discharge increases rapidly. According to the partial discharge characteristic parameters of creepage discharge, the whole creepage discharge process is partitioned into four stages. Compared with unaged HTV silicone rubber, the aged HTV silicone rubber has less fluctuation in performance parameters and a clear trend. The study found that UV aging not only affects the physicochemical and hydrophobic properties of the HTV silicone rubber, but also accelerates the development of creepage discharge under AC voltage.