High Frequency Loss From Neutral Wire-Shield Interaction of Shielded Power Cable

The conductor and ground shield layers of shielded distribution cable provide a smooth interface between conductors and insulation. Their semiconducting nature causes attenuation of high frequencies which propagate down the cable, as the high frequency displacement current flows through the shield layers and, in the case of concentric neutral cable, in a circumferential direction through the ground shield to a neutral wire. Such attenuation is relevant to partial discharge detection and the use of shielded power cable for wideband communications. This paper discusses the high frequency attenuation in concentric neutral shielded power cable and develops an analytic approximation for predicting high frequency attenuation which is compared with finite element computations and experimental data.