Digital protection of LVDC and integration of Distributed generation

Abstract

Depletion of commercial energy sources and many advantages of Renewable Energy Sources (RES), more research is emphasis on RES and its components. Generation by RES is generally distributed by using low voltage DC (LVDC) distribution. It is very essential to protect components of LVDC from fault and abnormal conditions. Switchgears/ Protection devices are used to isolate healthy part of electrical system from faulty network, by using various fault detection and control mechanism. Generally protection is given to the grid which integrates RES and existing grid provides power to load. At the occurrence of fault, faulty bus goes out of operation and source which is working in normal condition also disconnects from the load. So in order to maintain supply continuity, it is necessary to provide separate protection for each RES which acts as Distributed generation. The proposed scheme for protection of a LVDC Distribution system in a microgrid, automatically detects fault and isolates the faulty section. It integrates source of the faulty bus with another source and also cascade load at same time of integration. This helps in maintaining supply continuity to respective load and under utilization of RES/DG. To fulfill characteristics such as fast interrupting time and high short-circuit current withstanding capability, solid state/digital switches such as MOSFET, IGBT, etc can be used. The proposed said scheme is verified by MATLAB Simulation.