Optimal planning of autonomous micro-grids

Distributed Generators are gaining significant importance in bridging the gap between limited generation capacities and steeply increasing demands. Micro-grids are slowly replacing distribution systems in view of satisfying the needs of select customers without compromising the quality of power. In this regard, an optimal planning has been attempted in this paper in view of transforming an existing radial distribution system into an autonomous micro-grid. An algorithm has been developed to identify the optimal locations of DG units to be placed in the distribution system, based on certain performance indices and also an optimal sizing methodology for the DG units has been formulated. This paper also suggests an optimal structure for the transformed autonomous micro-grid taking into account the reliability issues of the micro-grid and it is found that, weakly meshed architecture is best suited. The Particle Swarm Optimization technique has been used for validating the proposed planning methodologies. The standard 33 bus radial distribution system has been adopted for validation.