Development of On-line Partial Discharge Monitor System for XLPE Power Cable

High voltage XLPE power cable is a very important part of power system. Partial discharge (PD) can play as a prominent indicator of insulation defects. Series of online and offline PD detection methodology has been developed. In order to preserve high frequency component of PD signals, DSP based feeder terminal unit (FTU) is proposed to be installed on site to detect PD of power cable. Thereafter, analog input is first converted to digital signals, then PD signals can be identified with wavelet analysis and the PD signal for each time span can be transmitted to host for data log and analysis in controlling center through wide area network (WAN) or power modem. The proposed system has the advantage reliability and flexibility besides wide analog bandwidth