Evaluating the effects of renewable and non-renewable DGs on DNEP from the reliability, uncertainty, and operational points of view by employing hybrid GA and OPF

Abstract

SUMMARY This paper proposes an approach to evaluate the effects of renewable and non-renewable distributed generations (DGs) on distribution network expansion planning from the reliability, uncertainty, and operational viewpoints. This methodology aims to determine the optimal capacity reinforcement of distribution network to meet the load growth in the planning horizon subject to the technical and operational constraints in the presence of utility-owned DG units. The capacity reinforcement includes determining ‘the expanded capacity of existing medium voltage (MV) lines as well as high voltage/medium voltage (HV/MV) substations’, ‘the capacity of new MV lines (feeders) and HV/MV substations’, and ‘the site, capacity and generation schedule of DGs’. To precisely calculate the operational and interruption costs, the variation of load is regarded using the annual load duration curve. Also, the uncertainty of the load, energy price, and the power generated by renewable DGs have been considered. The possibility of islanding and also the load transferring through the reserve feeders have been regarded in the problem to improve the reliability of network. The proposed approach has been formulated as an optimization problem where a hybrid genetic algorithm and optimal power flow is employed to solve it. Finally, the proposed method is applied to the 54-bus test system in different scenarios and the results are discussed. The simulation results show the effectiveness of the presented method. Copyright © 2014 John Wiley & Sons, Ltd.