A Novel Variable-frequency Resonant System for Partial Discharge Detection of XLPE Cables

Cross-linked polyethylene (XLPE) cables play an important role in power network. Partial discharge (PD) detection is one of the most conclusive indicators of defects and the ongoing degradation process for XLPE cables. But the traditional variable-frequency resonant system cannot used for PD detection, because of the disturbance produced by the inverter. In this paper, a novel variable-frequency resonant system using Equivalent Pulse Width Modulation, Time Domain Elimination and Time Domain Reflection (TDR) is presented. The novel system is suitable for the withstand test as well as PD detection test. The laboratory testing results prove the feasibility of the system.