Influence of surface discharge on the deterioration characteristics of ethylene‐propylene rubber cable insulation under alternating current high voltage

To investigate partial discharge-induced deterioration characteristics of ethylene-propylene rubber (EPR) cable insulation under repeated alternating current (AC) voltage on high-speed trains, an experimental platform with a column-plate EPR model is established. The surface condition and breakdown samples after discharge treatment are observed measured. In addition, fitting formula to evaluate the extent proposed. results show that pretreatments, volume resistivity increases first decreases afterwards when magnitude low. When (PD) intensity 100 pC, decrease monotonously, decreasing rate positively correlated PD intensity. During pre-treatment, white circle appears near electrode turns pale yellow For pretreatments 50 withstand increase afterwards, downward trend slow. pre-treatments 200 400 significantly degradation time. shows action strong electric field, relationship between reliability samples, probability molecular chain breakage, activity not linear.