Analysis of Partial Discharge Measured on Field for Cable Joint

In order to measure partial discharge of power cable joint on field, this paper introduces a testing system base on the pulse polarity discrimination method. Part discharge of cable joint has been measured at several sites by this system. Analysis of data show that the system can eliminate disturbance out of the cable joint, and obtain true PD signal with anti-jamming methods, such as pulse polarity discrimination, wavelet analysis, threshold Setting. So it can provide available date to evaluate insulation status of power cable joint.