An interactive dispatching strategy for micro energy grids considering multi-energy flexible conversion based on the three-level optimization perspective

The study considered the optimization problem of micro energy grids (MEGs) participating in a bidding game with a utility energy grid. To begin, multi-level bidding game frameworks made of multi-MEGs were designed at different stages (day-ahead, intra-day, and real-time), and a three-stage optimization model with multiple game status was present in this paper. Secondly, the paper proposed an improved ant colony optimization algorithm based on the adaptive adjustment of pheromone volatile factor and transfer probability. The IEEE37 node distribution system and the eight-node natural gas system are selected for example analysis. The results show that: (1) the proposed multi-level bidding game strategy can establish the optimal scheme of multi-MEGs operation at different stages of day-ahead, intra-day, and real-time; (2) the improved ant colony optimization can consider the differences of the cooperative game and non-cooperative game among different entities, balance the multi-objective appeals of energy supply cost, output fluctuation of a wind power plant (WPP) and photovoltaic power (PV), bidding revenue, and reserve cost, which could help obtain the global optimum solution; (3) the price-based demand response is more effective in converting renewable power into different forms of energy, and in participating in bidding transactions with the utility energy grid. A more liberalized energy market will bring higher bidding revenue for multi-MEGs.