Research on Propagation Characteristics of Partial Discharge Signal in Cable Joint Based on CST

The purpose of this article is to study the propagation characteristics of cable joints. Using partial discharge signals to reliably locate the fault location is one of the popular cable fault detection methods. However, the partial discharge signal is prone to attenuation and distortion when it propagates in a power cable or a cable joint. From the perspective of scattering parameters, this paper first used the CST software to calculate the scattering parameters of the cable joint. Then, using the relationship between transmission line characteristic parameters and scattering parameters, the attenuation constant and phase velocity were obtained. Finally, in order to ensure the reliability of the simulation results, the vector network analyzer was used to measure the scattering parameters of the actual cable joint. From the analysis of the results, it could be seen that due to the complexity of the cable structure, the attenuation constant increases with frequency and is accompanied by spike-like jitter. The phase velocity has obvious fluctuation in the low frequency range, and basically remains unchanged in the high frequency range.