Two-stage Robust Economic Dispatch of Multi-microgrids under Expected Scenario

Abstract

With the increasing number of microgrids (MGs) connected to the distribution network system (DNS) in the region, the multi-microgrids (MMGs) is built in recent years. MMGs can effectively carry out energy interaction among MGs and improve the utilization rate of renewable energy. However, uncertainty will affect the energy interaction between MGs and the operation of MMGs. To solve this problem, a two-stage robust optimization (TRO) scheduling model for MMGs under expected scenario is first proposed in this paper. In the first stage (the uncertainty is unknown), the first-stage decision variables are obtained by taking the minimum operation of MMGs as the optimization objective in the expected scenarios, and then the robustness of the first-stage decision variables is determined by the robust test model (RTM) under the given uncertainty set. RTM is transformed based on two-stage zero-sum game theory and dual theory, a column and constraint generation algorithm (C&CG) is first used to test the robust feasibility of the first-stage decision variables. In the second stage (the uncertainty is known), the proposed model can obtain the second-stage decision variables without changing the first-stage decision variables. Case studies verify that the proposed model can effectively solve the impact of uncertainty on system operation, and has lower operation cost than the non-interactive MMGs.