A multi-objective two-stage cooperative model for considering economic and flexibility perspectives

This paper presents a two-stage multi-objective framework for optimal operation of modern multi-area microgrids (MAMGs) taking into account cost and flexibility as objective functions. The MGs accommodate both non-dispatchable distributed energy resources (wind turbines and photovoltaic systems) and dispatchable ones (battery energy storages, fuel cells, microturbines, and diesel generators). The MGs have demand response capability, and they could also have peer-to-peer power exchange together. The first stage focuses on total operation cost minimization of set of MGs in a cooperative operation manner, while the second stage maximizes the flexibility of MGs so that the first-stage costs do not exceed a predefined limit. To evaluate the flexibility level of MGs, a novel index has been defined to compare the average flexibility of MGs during the peak load period. The proposed model is compared with the decentralized operation manner. The simulation results reveal the superior performance of the proposed framework compared to the decentralized one in terms of economic, flexibility, and reliability aspects. • A multi-area microgrid system is modeled. • The economic and flexibility objectives is considered. • A cooperative energy management approach is developed. • A novel dynamic flexibility index is designed to quantify the available flexibility.