Characterizing the temperature dependence of the contact resistance in substation connectors

Abstract

The electrical resistance, and in particular, the electrical contact resistance (ECR), plays a critical role in the electrical and thermal behaviors of substation connectors. Despite its impact, there are very few research works analyzing the temperature dependence of the ECR and its terms, the constriction and film resistances. It is very important to understand the contribution of the ECR to the total resistance, and its dependence on temperature. This work studies these dependences in detail by analyzing two types of connectors, i.e., connectors intended to join tubular bus bars, and connectors for stranded conductors. Due to the specific features of bus bars and stranded conductors, the ECR of both conductors has a different impact on the total resistance. The experimental approach presented in this work can be applied to better understand the role of the contact resistance, allowing the design of improved and more reliable substation connectors and similar devices.