Study On Safe And Stable Control Of Access System Of Yichun Thermal Power Plant

Thermal power plants have become very popular in the north due to low temperatures.When accessing system,a thermal power plant Power Grid will generate a large amount of surplus electric power into main network finally via each cross section,in case of comparatively large installed capacity and small regional load.For example,yichun thermal power plant is located in wumahe district,yichun city,heilongjiang province.Heilongjiang power grid is located in the north of northeast power grid,and the main grid frame is composed of two levels of voltages of 500 k V and 220 k V,which can be divided into four parts:eastern power grid,central power grid,western power grid and northern power grid.When the power plant of yichun thermal power plant is connected to the system,under normal operation and maintenance mode,the connection lines and other power equipment around it may be overloaded.Therefore,it is necessary to solve the problem of thermal stability and synchronous stability of power transmission and output analysis system.This thesis discusses and studies the following points:(1)this thesis analyzes the general situation of northeast power grid,heilongjiang power grid and yichun thermal power plant,and analyzes the operation sequence of yichun thermal power plant,load installation planning and power balance in yichun and hegang.(2)this paper models the system components of the power grid and the operation mode of the power grid of yichun thermal power plant,and introduces the power flow calculation method of the power system network.(3)in this thesis,the power system simulation software PSASP is adopted,and the Newton raphson method is used to calculate the simulated power flow of the power grid of yichun thermal power plant,and the fault point is set on the nearby line to output the public Angle characteristic curve of the nearby power plant.(4)the simulation results are analyzed,and the solution to the overload problem and synchronous stability problem is proposed,which can effectively avoid the occurrence of power outage accident and reduce the operation and maintenance cost of the power grid as much as possible.The study of this thesis has a certain theoretical and practical significance to further research on accessing system of all large thermal power plants.