A Framework for Optimal Coordinated Primary-Secondary Planning of Distribution Systems Considering MV Distributed Generation

Power distribution planning (PDP) approaches are evolving to new models and methods by introduction of smart grids. Distribution system is divided into two levels: 1) medium voltage (MV) as primary network and 2) low voltage (LV) as secondary network. In PDP, to have a comprehensive view, costs of primary and secondary networks must be considered coordinately. The PDP problem is exacerbated incorporating distributed generators (DG). In this paper, a single cost function is proposed, which comprises costs of LV feeders, MV substations, MV DG, MV feeders, and high voltage substations; imperialist competitive algorithm is utilized to minimize the cost function; and a greenfield network is planned for a long-term period. Results show that in PDP problem, incorporated with DG, it is required to coordinately plan the primary and the secondary network.