Research On Distribution Network Resilience Restoration Strategy Considering Flexibility Resources In Source-grid-load

With the complex development of the power system,natural disasters,manmade accidents,and other extreme events frequently lead to large-scale power outages in the distribution network,posing a serious challenge to ensuring continuous and reliable power supply to the load.Additionally,to cope with the dual crisis of energy depletion and environmental pollution,a large number of distributed renewable energy sources and electrical energy replacement loads are integrated into the distribution system,and integrated energy systems are being vigorously developed to improve energy utilization efficiency.These flexible resources can not only effectively improve the reliability of the distribution system during normal operation,but also provide solutions for load restoration of the distribution system during low-probability-high-impact disasters,which is of important value for enhancing the distribution network resilience.However,current distribution network resilience research is still in the initial stage of exploration.On the one hand,the source-load fluctuation characteristics are highlighted due to the large number of distributed generators and flexible loads connected to the grid.The characteristics of distributed resources under extreme events such as natural disasters are difficult to be accurately portrayed and effectively controlled,which may lead to more serious system safety and stable operation problems.On the other hand,park-level integrated energy systems will be developed rapidly because of their multi-energy complementary,environment-friendly and high-efficiency characteristics.How to coordinate it with energy storage and new energy to participate in post disaster load restoration needs to be further studied.Existing resilience studies are still insufficient to consider energy coupling.The interconnection and deep coupling of multiple energy networks make it difficult to make reasonable decisions at the planning and operation levels and difficult to achieve the optimal distribution of electric energy in the spatial and temporal dimensions.Therefore,it is important to study the resilience restoration strategy of distribution network with source-grid-load flexibility resources to improve the system’s power supply guarantee capability.To this end,this paper focuses on the resilience restoration strategy of the distribution network in the context of energy interconnection.The main work is as follows:(1)The energy interconnection distribution system component models are established.The characteristics of flexibility resources such as new energy units,mobile storage devices,and controllable loads are described in detail from the perspectives of extreme scenarios,energy coupling and emergency power supply demand.(2)A two-stage robust restoration strategy considering the pre-layout and dynamic dispatch of mobile energy storage is proposed,taking into account the uncertainty of PV power output and network reconfiguration.In the pre-disaster prevention stage,a pre-disaster robust optimization model is established.The column and constraint generation algorithm is used to solve the siting and capacity scheme of mobile energy storage.In the post-disaster restoration stage,a mixed-integer second-order cone planning model for cooperative restoration of multiple sources is established,considering the impact of the disaster on the traffic network access time.(3)To address the uncertainty of PV output under the ice disaster scenario,a data-driven distribution network resilience restoration strategy is proposed.After the disaster,flexible resources such as mobile energy storage and park-level integrated energy system and PV units are used to dynamically restore critical loads.Historical data features are extracted and PV output scenarios under ice disaster are generated by the proposed improved conditional generative adversarial nets.On the premise of meeting the constraints of emergency microgrids and load demand,the optimal mobile energy storage configuration and controllable power scheme output are achieved.(4)Finally,case studies are carried out on the improved IEEE 3 3-bus system and PE&G 69-bus system.The simulation results show that the proposed strategy in this paper can make full use of the advantages of source-grid-load multi-source collaboration and reduce the risk of large-scale power outages in the pre-disaster and post-disaster stage of the distribution network,which can provide useful references for improving the distribution network resilience.