Design And Simulation Of Traction Power Supply System For Suburban Railway

City railway is a passenger transport system serving the city,and its service range is between medium and long distance.There are many problems existing in the city railway,such as large investment in external power supply,more regenerative braking energy,large instantaneous power of the system,and high departure density when the train is disconnected.In order to meet the power supply capacity of the system,improve the system performance and save investment,it is very important to choose the appropriate power supply scheme.Therefore,the power supply scheme based on SVG and traction cable are studied in this paper.The comparison between the two kinds of Fangna and the traditional power supply scheme provides a reference for the selection of traction power supply scheme of city railway.The scheme of traction power supply based on SVG for City railway is studied.In this paper,the operation mode of fixed standby traction substation in the near future and all traction substations in the long term is put forward.Then the model to analyze the relationship between the distance of power supply arm and SVG capacity under different working conditions in the near and long term is established.And the model is solved and verified,then the relevant design of the scheme is discussed.The power supply scheme based on traction cable is studied in this paper.In this paper,the model is established to solve and analyze the arm distance of two side power supply and one side power supply.A hierarchical interactive iterative power flow algorithm is proposed in this paper,which is suitable for the traction cable through power supply system.The general model of traction cable through power supply system based on line is introduced in this paper.The specific solving steps of the algorithm are introduced in detail.This algorithm can improve the operation speed by hierarchical reduction.Next,the city railway AC traction power supply system simulation software(ACTPS)is introduced.The software is developed with visual studio,and the object-oriented programming method is used to realize the simulation of different power supply schemes.Finally,taking a city railway in China as an example,the load process simulation and analysis of traditional power supply scheme,SVG based power supply scheme and traction cable through power supply scheme are carried out based on operation diagram.The simulation results and economic analysis show that compared with the traditional power supply scheme,the SVG based power supply scheme and the traction cable through power supply scheme can effectively improve the system performance,and the traction cable through power supply scheme can achieve the maximum utilization of regenerative braking energy.When the regenerative braking energy of the train is large,and the traditional power supply scheme and the SVG based power supply scheme need more external power,the traction cable through power supply scheme has better economy.