Reducing multiple estimation for fault location in medium voltage distribution networks

Abstract

Short circuits are a matter of major concern in the protection of power distribution systems. They can lead to interruptions in energy supply, and consequently affect the quality of power delivered to consumers. In these situations, there is a need to determine a fault location to ensure that a technical crew can reestablish the system as fast as possible. However, in radial distribution networks, fault location is not a trivial task, as the presence of lateral branches will result in multiple estimations. In this context, the present article addresses the problem of multiple estimation, considering the response of an impedance-based fault locator. To validate the proposed analytical approach, the IEEE 34-node test feeder was used. Moreover, the approach was analyzed in terms of: (a) the percentage reduction of the multiple estimation regions (R%); (b) the number of meters allocated in the feeder; and (c) the distance errors estimated by the fault locator. The results demonstrate that the proposed formulation allowed a minor influence of errors deriving from the impedance-based fault locator and a good trade-off between the number of meters (investment) and the R%.