Safety And Stability Checking Analysis Of 500kV Beipo-Keshi-Lingjiao Transmission And Transformation Project

With the rapid development of China’s technology and economy,people’s demand for electricity has become larger and larger,and the society’s requirements for safety,economy,and high-quality electricity use are getting higher and higher.Accelerating power grid construction,improving power transmission capacity,and building reliable ultra-high voltage and extra-high voltage transmission corridors are necessary measures for the power grid.On the revitalization road of the old industrial base in Northeast China,the power demand of the Northeast Power Grid has also grown rapidly.The construction of new EHV transmission lines is the best choice for the Northeast Power Grid.The safety and stable check of the new transmission lines before they are put into operation is the top priority.This paper studies and analyzes the safety and stability check of Beipo ~ Keshi ~ Lingjiao 500 k V power transmission and transformation project before commissioning,analyzes the structure and operation mode of the grid after the project is put into operation,and finds out the problems that may occur after the project is put into operation and their corresponding solution.This paper starts with the power situation of the power grid of Beipo ~Keshi ~ Lingjiao 500 k V power transmission and transformation project,analyzes the power shortage in Lingjiao area,and clarifies the power source of the shortage.Then this paper analysis of different connection modes between the 220 k V power grid and the Keshi area power grid.Among them,this paper proposes four power flow modes for the 500 k V/220 k V electromagnetic ring network unwinding and ring-closing operation modes in Keshi to Lingjiao area,and carries out power flow calculation,overload analysis,synchronous stability analysis and voltage stability analysis and frequency stability analysis through PSASP software respectively.And then this paper indicates the types of faults that may affect the safe and stable operation of the system,and corresponding solutions are given.This paper compares and analyzes the simulation results of various powerflow modes,with the load limit of Lingjiao area,the single fault causing the isolated network,the low voltage problem and the new safety equipment as indicators,pointing out the recommended operation mode after the Beipo ~Keshi ~ Lingjiao 500 k V power transmission and transformation project is put into operation,and performs short-circuit current verification for the grid structure under this operation mode.This conclusion can ensure that the Lingjiao power grid in Beipo-Keshi-Lingjiao 500 k V power transmission and transformation project can maintain safe and stable operation,and also can reduce the risk of disbandment operation faced by the power grid in this area as much as possible.