Reliability study of a micro grid system with optimal sizing and placement of DER

Microgrids comprise a network of small scale distributed energy resources (DERs) like fuel cells, micro turbines, PV arrays and wind turbine etc. and energy storage devices. Current deregulation regime is encouraging open competition amongst the small/medium utility service providers in providing quality and reliable ´clean´ power to the customers at an economic rate. Economic power production is related to higher operational efficiency of the generating and distribution systems. In the reforming process, taxes and penalties imposed on the tariff system, like environmental pollution tax, contracted failure penalties etc. are posing problems for the fossil fuel plants. Microgrids with environment-friendly DERs have an edge over such problems. Microgrids also reduce line loss and CO₂/NO_x emission, increase overall energy efficiency through CHP operation, relieve T&D congestion and defer investments to upgrade existing generation. However, all these benefits could be achieved if DERs of the Microgrids have optimal size and location. This paper presents particle swarm optimization (PSO) technique to determine optimal size and location of the DER in a meshed network for maximizing the economic benefits by minimizing the line loss.