MV Cable Accessory Research
Evaluation of 35-kV terminations
Medium Voltage (MV) cable accessories are used to terminate, join, or connect power cable and to manage electrical stresses. One challenge faced by utilities is assuring the reliability and maximizing the expected life of these components. EPRI has research underway to raise industry understanding and awareness of the function of cable accessories, and to illustrate the impact of various workmanship approaches on the anticipated performance of cable accessories as determined by the presence of partial discharge (PD).
This section describes a multi-year project investigating the performance of medium,voltage (MV) cable terminations. The function of a cable termination is to provide stress control at the cable shield terminus and separation between the cable shield and exposed conductor for external leakage insulation. In order for cable terminations to effectively control electrical stresses, they must be designed to do so at expected operating voltages, and built meticulously to specifications, as minor differences in workmanship may influence-electrical stress control efficacy. Some utilities have experienced in service failures of cable terminations operating at 35kV, and forensic examination has shown that termination designs and preparation practices may have been contributors. In this research, EPRI has performed research to better understand the contributors to in-service failures of MV terminations, and to understand and illustrate the impact of various workmanship approaches on the anticipated health of cable terminations, as determined by the presence of partial discharge (PD). The research was focused on 35 kV cable terminations, as higher operating voltages exacerbate the internal breakdown that will occur with the presence of partial discharge. Both heat shrink and cold shrink termination kits were examined. The cable type utilized for study was a 750 Al XLPE insulated cable with a strippable semiconducting insulation shield
Here is an update video describing MV Cable termination testing underway at EPRI’s Lenox Laboratory.
3002016384: MV Cable Accessory Research: 35-kV Termination Investigation
3002018965: MV Cable Accessory Research: 2020
3002021661: Medium Voltage (MV) Cable Accessory Research: 2021