Research On Self-healing Control Strategy Of Smart Distribution Grid Based On Finite State Machine

Sustainable development of national economy depends on sufficient power supply.Distributed generation interconnection and related technologies have been developed rapidly to ensure the security of national energy supply.Intelligent grid arises at the historic moment,and distribution network is one of the most important parts of intelligent grid.Distribution network is directly oriented to end users,and the diversity of users and power loads determined the complexity of distribution network.Therefore,it is significant to research the application of smart grid,especially for intelligent distribution network.Self-healing control technology is the core of intelligent distribution network,which can quickly achieve fault diagnosis,fault location,fault isolation and power supply recovery when the distribution network fails.And the operation state can be evaluated to make the distribution network run in the optimal state after the fault recovery.A hierarchical coordination control framework is established,which is consisted of decision layer,coordination layer and equipment layer containing distributed generation.In view of the characteristics and objectives of intelligent power distribution network and selfhealing control,the theory of multi-agent system is introduced into the research of power supply restoration of distribution network based on the "2-3-6" self-healing control framework of intelligent distribution network,which improves the self-healing ability of intelligent distribution network to cope with complex operating environment.A state transition model of self-healing control for intelligent distribution network is proposed based on Finite State Machine(FSM).In order to realize effective prevention from faults,cut-off the fault quickly and power supply recovery from power loss load in intelligent distribution network,established a composite FSM based on executable events and controllable variables for multiple FSM parallel operation,and applied to state transition of self-healing control system of intelligent distribution network,determined the operation state transition control schemes of intelligent distribution network self-healing control system.A self-healing method based on multi-agent systems(MAS)for power supply recovery of intelligent distribution network with DG is proposed.Through the switch operation of feeder,changed the configuration of distribution system,to restore the power supply in the fault zone.This thesis puts forward four kinds of agents: feeder agent,regional agent,switch agent and DG agent.The agents can communicate and cooperate with each other to restore power supply in the maximum range of distribution network.A comprehensive vulnerability assessment method for intelligent distribution network based on Radial Basis Function(RBF)neural network is proposed.And studied the influence of wind power access on power grid vulnerability.Realizing the self-prevention ability of selfhealing control of intelligent distribution network.Basis of various vulnerability assessment indexes of distribution network,the vulnerable links in the network are identified,vulnerable nodes and branches are found,and optimization and preventive measures are taken to improve the reliable operation of the grid.