Protection system for future LV microgrids

Abstract

Traditional protection of low voltage (LV) network will not be applicable for future LV microgrids and new adaptive protection system must be developed. In this paper adaptive protection system for LV microgrid during normal and island operation will be presented. Adaptivity means that protection system will e.g. change settings of LV feeder protective devices (PDs) according to the operation state of the LV microgrid, i.e. normal or island operation, and in the settings of LV feeder PDs also the number and type of DG units connected to the corresponding LV feeder and also their fault current feeding capabilities will be taken into account. Fast and selective operation between different PDs is achieved by intelligent utilization of high-speed communication.