PD location and interference suppression method of power cable based on cross-correlation

A novel PD identification and location method based on cross-correlation is proposed in paper. The method aims to solve the problem of weak signal identification and interference suppression. Taking advantage of the characteristics that the time axis of PD pulses at both ends of the cable is symmetrical and the interference signal is asymmetric, the cross-correlation computation is carried out through the alignment of reference pulses, so as to suppress the interference effects such as corona. In the calculation of basis PD pulse time difference, the synchronous pulse actively injected is used to shorten the data time window and reduce the influence of noise, and the accurate time difference is extracted through generalized cross-correlation. In this paper, the above methods are verified by simulation and experiment. The analysis results show that the interference can be suppressed and the weak signal recognition ability can be improved through multiple correlation operations, which lays the foundation for accurate PD location.