Real-time wireless, contactless and coreless monitoring of the current distribution in substation conductors for fault diagnosis

Abstract

Parallel conductors are found in electrical transmission and distribution systems including large ampacity feeders or loads. However, current unbalance often occurs, especially in alternating current systems. This non-regular current distribution causes overheating and premature ageing, facilitating the occurrence of failures. Therefore, a fault diagnosis system is a must, which can be performed by monitoring in real-time the individual currents flowing through the conductors. In this paper a setup including three parallel aluminum conductors of large cross section, a spacer and two terminal substation connectors is analyzed. A real-time, wireless, coreless and contactless system based on three low cost Hall effect sensors is proposed, which is also easy to install. Experimental results, which include fourteen cases, comprising thirteen fault modes and a well installed set, prove the suitability and potential of the proposed approach, since it allows a correct real-time detection of all analyzed faulty conditions as well as the detection of currents exceeding the thermal rating of the conductors.