Electrical tree initiation characteristics under repetitive rate pulse in epoxy resin

Electrical aging of insulation materials affects the reliability and security of pulsed power equipments. Based on the present pulsed source, the electrical tree initiation characteristic of epoxy resin is studied under different frequencies (1, 25, 50, 100, 300 and 500 Hz). The parameters of the pulsed source are as follows: peak voltage about 34 kV, rise time about 40 ns and half pulse width about 70 ns. The relationship between epoxy resin aging and voltage frequency is studied. Experiments demonstrate that tree initiation voltage decreases as frequency increases. The initiation voltage under positive pulse is higher than that under negative pulse. Insulation characteristic of E44 is better than that of PMMA. Factors influencing electrical tree initiation characteristic of E44 are discu