Robust high voltage cable joint design

Abstract

Rapid growth of Indian cities calls for power transmission and distribution through underground networks. The reliability of the underground power transmission is largely dictated by the performance of cable joints. Currently, the installation of cable joints is being performed by skilled and experienced jointers. Since the reliability of cable joints not only depends on the design but also attributed to workmanship, the present paper aims at establishing a robust design methodology to minimize the dependency of skilled jointers. The performance of the cable joints is related to e-field concentration which is essentially result in partial discharges. The e-field concentration in cable joints is attributed to several variables such as (1) stress cone radius and geometry, (2) faraday cage design and edge radius, (3) ground clearance, and (4) creepage distance between faraday cage and stress cone etc. The relationship between the above parameters to the e-field is studied in detail by using FEM package: ANSYS Maxwell. Besides, robust design space is established through performing design of experiments (DOE). The transfer function, derived through DOE, indicates a non-liner relationship with the above design parameters. The transfer function is validated through high voltage tests for partial discharge and AC withstand test on two different cable joint designs.