A Novel High Frequency Circuit model of Power Cable Joint

In this paper, an improved high-frequency equivalent circuit model is developed to represent the joint high-frequency behavior for the time and frequency-domain analyses. The model is based on improved high-order multipler sections. Considering the shape variation in axial direction, the cable joint can be approximated as series-connected uniform line pieces, each of which can be equivalent as several high-order Gamma sections. By using vector fitting (VF) method, the equivalent circuit parameters are extracted from calculated impedance and admittance in unit length which are obtained through measured geometrical dimensions and material properties. The parameters of circuit model parameters are easy to obtain with robustness. The model can be efficiently implemented in the time domain simulation of PD propagation characteristics and precisely PD locating in power cable system.