A multi-stage resilience optimization method for electricity-gas coupled distribution networks based on islanding division

With the increasing penetration of natural gas in power systems, the resilience of electric-gas coupled distribution networks under extreme fault perturbations has received increasing attention. Since the entire phase resilience of an electric-gas coupled distribution network after an extreme event depends on its system function, it is necessary to consider a multi-phase recovery process in order to comprehensively improve the resilience and rapid recovery of electric-gas coupled distribution networks against extreme events. In this paper, a fast fault isolation and service restoration methodology that integrates active islanding effect and RCS is proposed to improve the resilience and fast recovery capability of electric-gas coupled distribution networks. Firstly, an electric-gas coupled distribution network model is constructed, after which the multi-stage recovery process is modeled in detail by combining the dynamic mechanism of the load supply curve of the electric-gas coupled distribution network under the whole process of extreme faults, including the topological constraints and power constraints of each stage and the coupling relationship between each stage. The effectiveness of the proposed multi-stage resilience optimization method is verified using the IEEE33 node power system and the natural gas 7-node distribution system as examples. It is demonstrated that the multi-stage restoration method proposed in this paper can greatly improve the resilience of coupled electric-gas distribution networks.