Abstract:
Microgrid, as the most important part of the grid, is susceptible to extreme natural disasters or equipment failures, because it relies on renewable energy for power generation. In order to enhance microgrid resilience and effectively control the adverse effects of faulty units, this paper presents a hierarchical nested predictive control (HNPC) strategy for multi-microgrids system with electric vehicles (EVs). At nested structure layer, the microgrids are divided according to different types (household, commercial, industrial, etc.) and nested according to different load levels to reduce the impact of the faulty unit. When the microgrid with critical load is under fault condition, the nested structure can preferentially meet the power balance of this microgrid. If the microgrid with normal load failures, this structure will allow the microgrid at inner level to avoid the effect of fault hazard. Hence, the influence of microgrid failures can be reduced, and the safe operation of key microgrid can be guaranteed. At central scheduling layer, EVs can participate in this energy scheduling through connecting the EV aggregator and play the advantages of rapid charge and discharge in the vehicle-to-grid (V2G) regulation to help the system to meet the power balance. Through the comprehensive coordination of the main grid and the EV aggregator, a rapid power support to the microgrid under fault condition can be guaranteed to avoid the whole system collapse in the short term. According to the information obtained from the nested structure layer, microgrids can exchange power with each other to get reliable power supply in the long term. The random programming method is used at central scheduling layer to achieve the entire multi-microgrids integrated power deployment, and enhance the multi-microgrids resilience. The simulation results show that the method proposed in this paper can provide a reliable energy supply to the fault state of microgrid, meet the power balance, reduce the impact of the failure, and ensure the safe operation of the multi-microgrids system.