Research On Control Strategy Optimization For Automatic Switchover System Of Regional Power Grid

With the development of social economy,the structure of power grid is becoming more and more complex,the demand for power supply and reliability of power supply are getting higher and higher in all walks of life.Automatic bus transfer device can effectively solve the problem of restoring power supply after power grid failure,but it can only achieve local control strategy and cannot adapt to the changes of power grid operation mode.The existing dispatching automation system technology has been able to provide reliable technical support for automatic switchover system of regional power grid.The automatic switchover system of regional power grid has obvious advantages over the automatic bus transfer device in the station.However,the development of regional power grid automatic switchover system is still limited by the large number of distributed generations connected to the distribution network and overload problems.This paper describes the basic structure of the regional power grid automatic switchover system.Starting with the two-terminal power supply network structure adopted by most of the existing distribution networks,the control strategies of automatic switchover system under different fault conditions are analyzed.At the same time,considering the influence of distributed generation interconnection on the control strategy of regional power grid automatic switchover system,a control method of regional power grid automatic switchover system considering distributed generation interconnection is proposed.Through the cooperation of the stabilization device and the automatic switchover system,the distributed power supply with load can meet the quasi-synchronous grid-connected conditions as far as possible,and the power supply after failure can be reasonably restored without sacrificing the distributed power supply with load.Aiming at the overload problem that may occur after the automatic switchover system operation,this paper proposes a control strategy optimization algorithm based on the combination of graph theory and GA-PSO algorithm.The graph theory method is used to find the feasible restoration power supply path.Meanwhile,the idea of GA algorithm crossover and mutation is introduced to improve the standard PSO algorithm to solve the optimal control strategy of the system,so as to avoid the harm of overload problem to the power grid.The above method has been applied to a regional power grid.After nearly half a year's operation,the feasibility of this method has been verified and the reliability of power supply can be improved.