Down-conductor fault detection and location via a voltage based method for radial distribution networks

A method to detect and locate a high-impedance fault caused by a downed conductor on a distribution primary feeder cone is presented. The protection system in radial networks generally consists in placing current detectors along each feeder line. A down-conductor fault typically has a very low current values which is often not detectable by conventional overcurrent protection devices. The proposed method is not based on current measurement but instead on voltage measurements performed at MV/LV stations. This method may be particularly interesting if LV potential transformers are already present in the network. The method is divided into two steps. The first step consists in determining whether each sensor is above or below the fault. The second step consists in determining the fault section, from a purely topological method. EMTP simulations are presented to highlight the effectiveness of the proposed technique.