Flashover properties of polymethyl methacrylate and nylon in coaxial electric field under nanosecond pulse voltage
It is executed to study flashover properties of polymethyl methacrylate and nylon 1010 in transformer oil in coaxial electric field by means of high voltage pulsed power supply SPG200 based on SOS switch.Flashover voltage of both solid dielectrics almost increases according to exponent following the linear growing inner electrode diameter,so do flashover voltage as well as flashover time lag versus flashover length almost linearly.polymethyl methacrylate doesn't take on higher flashover voltage than nylon 1010 in the experimental condition.Radial stress in coaxial electrodes focuses in the vicinity of inner electrode surface,as a result,flashover voltage under coaxial electric field depends on the electric intensity on the inner electrode surface and uniformity degree of radial electric field.Both increasing inner electrode diameter and prolonging flashover length can advance flashover voltage,but increasing inner electrode diameter is more interesting.