Two-Level Energy Management for Multi-microgrids Considering Degradation Cost of Energy Storage

In order to mitigate the interference and impact of the randomness and intermittency of renewable energy on distribution networks, and to effectively coordinate the energy mutual support among microgrids (MGs), this paper proposes a two-level energy management system (EMS) for a multi-microgrids (MMG). The lower-level aims to achieve optimal local economic operation of MGs, considering factors such as energy storage degradation cost and region-specific adjustable loads. The upper- level optimization model establishes an energy-sharing mode within the MMG based on the local microgrid power surplus/deficit, and minimize the total operating cost of local microgrids by adjusting the output of local controllable units. Under this mechanism, the overall economic operation of the MMG is achieved. This further reduces the interaction with the distribution grid, enhancing the autonomous operation capability while minimizing the impact on the distribution grid. Finally, we Simulating with three microgrids and mathematical models are established by using Yalmip and solved by using bmibnb. Simulation results demonstrate that the proposed EMS can reduce system operating costs and losses, greatly reduce the impact of MMGs on the distribution grid, and provide enhanced safety, reliability, and stability.