Microgrid formation strategy of distribution system considering regional power exchange constraints

When a contingency occurs in the distribution system (DS) due to extreme events, microgrid formation (MF) is an effective approach to reduce the impact of cascading phenomenon and enhance the resilience of DSs. The traditional MF methods follow the post-outage recovery criteria, which sectionalize the on-outage DS into multiple microgrids after the faults occur. However, if there is much power exchange between the DS and the microgrid, it will lead to fail for such recovery-oriented MF methods, reducing the capabilities of resilient DSs in resisting and rapidly recovering from an extreme condition. To further enhancing the resilience and risk-resistant performance of DSs in extreme conditions, this paper proposes a proactive networked MF method to restrict the regional power exchange prior to the extreme events and ensure the microgrids can be safely formed when the faults actually occur. Firstly, the photovoltaic (PV) parameters are obtained by using Monte Carlo method. Next, the active power output of the micro gas turbine (MT) and the energy storage system (ESS) is optimized to reduce the network losses. Moreover, power exchange between the microgrid and the other part of DS is constrained. The artificial bee colony (ABC) algorithm is utilized to solve the proposed model. Such MF strategy can effectively protect essential loads by optimally determining the lines to be cut. The effectiveness of the proposed method is validated with the modified IEEE 33-node distribution test system.