Research On The PD Detection Method Of HV XLPE Power Cable

Cross-linked polyethylene (XLPE) cable is now widely used ranged from 10 kV~500 kV thanks to its excellent electrical and mechanical properties. While, during the process of production, transportation and installation, there will be a variety of defects inevitably, which cause partial discharge, and then become the potential danger of safe operation of the power system. Based on the summarization of the previous XLPE cable PD detection method, we developed two kinds of PD detecting sensors, namely capacitance coupling sensor and inductance coupling sensor, which were employed to detect the typical PD signal, and then the pattern recognition of typical PD signal was carried out.In this paper, a software namely Ansys was employed to simulate the electrical field of six typical defects in order to determine the size range of defects, and typical defects were artificial simulated on the basis of the simulation results. The platform of PD test was set up, and two PD sensors namely capacitive coupling and inductive coupling were developed to detect the typical PD signals produced by the artificial defects, with the complement of amplifier, filters and other equipments, these two sensors can be used both in laboratory and in actual projects. Finally, the pattern recognition of typical PD signal was carried out. The results showed that the simulation typical defects was reasonable to produce PD signals, and the developed sensors both have good frequency responses, in which capacitive coupling sensor is more sensitive, but the inductive coupling sensor is more suitable for the practical engineering owing to its ease of installation. The six typical defects can be identified by extracting spectrum and phase spectrum of PD signal.