Development of the new partial discharge measuring method and device for long power cable using foil electrode

摘要

Partial discharge (PD) measurement is one of the most significant method for assessing the insulation quality of power cables, particularly for cross-link polyethylene (XLPE) insulation material. The capacitive coupling method has been widely applied for PD detection in cable lines. However, the detection sensitivity of this method drops due to attenuation of partial discharge pulsed during propagation. Therefore, we proposed a new method that can be applied to detect PD in the normal part of the cable, by considering the impedance of the shield electrode of the cable itself. In this research, a low voltage communication cable with a coaxial structure was employed as a transmission line. PD signal with a fix intensity was simulated using a pulse generator in connection with the cable line. A capacitive electrode made of metallic foil was placed onto the plastic jacket of the cable. As a result, a significant voltage was detected.