Research On Self-recovery Control Technology Of Intelligent Distribution Network

Distribution network,as a key link between power generation system and power users,is directly related to the security,reliability and economy of power supply.In recent years,with the rapid development of social economy,power users 'requirements for power supply reliability and power quality are gradually increasing.DG and new power loads,which mainly rely on renewable energy,are connected to the distribution network in large quantities,which brings more unknown factors to the safe operation of the distribution network.In addition,the global energy crisis and environmental damage caused by human activities are becoming more and more serious.Actively building a low-carbon,clean,safe,reliable,compatible and interactive smart grid has become the key for countries to meet challenges and achieve energy transformation.As an important part of smart grid,smart distribution network is the next development direction and goal of distribution network.Self-healing capability is the key feature of Smart distribution network,which can realize self-prevention and self-recovery of the system.Among them,self-prevention refers to finding potential risks in time through operation status assessment and taking measures to prevent and eliminate hidden troubles in time;self-recovery refers to the rapid completion of fault location and isolation when the system is disturbed or damaged by faults,and the completion of power supply recovery through power transfer.The realization of self-healing function of Smart distribution network is conducive to improving the quality of power supply and user experience,and ensuring the security,reliability and economy of system operation.On the basis of reading a lot of relevant literature,this paper studies the related technology of self-healing control in Smart distribution network.Firstly,the functions and objectives of self-healing control in Smart distribution network are studied,and a hierarchical,coordinated and interactive self-healing control system is established,and the basic issues related to self-healing control are discussed,which lays a solid foundation for subsequent research.Secondly,the reconfiguration strategy of Smart distribution network is studied.According to the different operation states and risks before the system failure,the corresponding self-healing control model and means are determined,which realizes the coordination among operation safety,economy and control speed,and improves the applicability of self-healing control scheme.Furthermore,the heuristic fast topology is studied for the limit state with high risk coefficient.Adjustment and load shedding strategy ensure the safe operation of the system under high-risk conditions.Finally,a comprehensive power supply recovery strategy is proposed.After the failure,the main network is restored by using hybrid multi-objective particle swarm optimization(MOPSO)algorithm with tie-line switching as the priority.Then,DG islands are used to divide the areas where the main network is not restored to realize the global restoration of power supply for non-fault outage load.In addition,numerical examples are used to verify the effectiveness and correctness of the proposed method.