Smart distribution grid multistage expansion planning under load forecasting uncertainty

The optimal distribution system planning (ODSP) is a complicated problem with multi-objective function and multi-constraints. The complexity of the problem is increased in smart distribution grids with uncertainties in both load and generation. In this study, problem of optimal smart distribution grids multistage expansion planning is presented in which reinforcement or installation time, capacity and location of MV substation and DER are taken into consideration. The binary global search optimization algorithm is proposed to solve the ODSP problem. The proposed cost function considers the capital investment, operation and the levelized energy cost (LEC) of each energy source. Loss characteristic matrix has been used for locating of MV substation and DER. The aspect of modeling under load growth uncertainty and multistage planning and multiple objective functions which are related to ODSP problem are considered in an integrated model. The multistage planning procedure is proposed to consider the pseudo-dynamic behavior of planning and continuing growth of demand. Load uncertainty is represented by point estimated approach and the results are compared with the Monte Carlo simulation (MCS). Presented methodology has been tested from base to long-term period on distribution network. The obtained results confirm the ability and validity of the presented method.