Important insights into steady-state calculations of voltages and currents in complex sheath bonding configurations of single-core cables

Abstract

Ensuring effective sheath bonding holds paramount importance within underground single-core cable systems, as a misjudged selection can precipitate cable failures or jeopardize human safety. The foundation of a sound bonding design rests upon a meticulous examination of induced voltages and currents on the cable sheaths. To address this, guidelines and numerical techniques have been introduced, applicable to both handheld calculators and sophisticated software tools. However, their precision hinges on specific features and solving techniques, aspects that remain unclarified in current literature. This paper delves into a comprehensive exploration of sheath current and voltage calculations at steady-state in single-core cable systems. A rigorous benchmarking exercise is undertaken, comparing bonding-design simulation results derived from various computation methods. Moreover, the study scrutinizes the impact of several parameters, shedding light on crucial insights. Building upon this, the paper proposes modelling recommendations for the design and assessment of sheath bonding configurations in complex power cable installations.