Two-stage robust distribution system operation by coordinating electric vehicle aggregator charging and load curtailments

Abstract

In this paper, a comprehensive two-stage robust distribution system operation model is proposed by adjusting the charging of electric vehicle aggregators (EVAs) and curtailing loads. Because uncertainties in EVA charging demands are involved in the second stage of the adopted two-stage framework, distributionally robust optimization is used to improve the average economic performance of the proposed model, and security of distribution system operation is guaranteed by applying the Farkas lemma and robust optimization. The proposed model is solved by iteratively adding optimality cuts and feasibility cuts through a novel constraint generation algorithm, whose mathematical Proof is provided. The case studies show that the proposed model is capable of properly handling EVA uncertainties and coordinating EVA charging and load curtailments. The optimal coordination depends on several key parameters including the cost coefficients of delaying EVA charging and curtailing loads, the limits on delaying EVA charging, the system load level, and the EVA uncertainty level.