Modeling And Simulation Of Electromagnetic Environment Of High-speed Railway Return System

Over the years,most of my country’s high-speed railways have been upgraded to electrification.High-speed railways are changing our daily lives.General rail transportation can no longer meet our daily travel requirements.High-speed railways have become our preferred travel choice.High-speed rail transit is an ideal means of transportation for modern travel,and it can also meet the travel needs of citizens,because high-speed rail has the advantages of fast speed,stable operation,and high reliability that ordinary railways do not have.With the continuous expansion of the scale of high-speed rail transit,the impact of high-speed rail transit as an electrical equipment connected to the grid caused by electromagnetic interference is increasing,so it is worthy of attention.With the continuous improvement of the high-speed railway network structure,the network environment has become more complex,so electromagnetic interference is becoming more and more serious,which may affect signal transmission and cause a certain degree of interference to the normal operation of high-speed railways.At the same time,electromagnetic interference It will also have a certain degree of impact on the human body.At the same time,according to the analysis and research on the effects of the railway electromagnetic environment,methods and measures to improve the railway electromagnetic environment are proposed.The main research contents of this paper are as follows:(1)Construct the electromagnetic field numerical simulation model of the 25 k V pantograph network under the autotransformer power supply(AT)mode,and study and analyze the electromagnetic radiation spectrum and energy distribution characteristics of the power frequency single-phase AC 22.5k V～27.5k V pantograph network;(2)Study and analyze the current characteristics and the intensity and frequency range of the induced electromagnetic field under the special operating conditions of the power frequency single-phase AC 22.5k V～27.5k V pantograph network train.The specific research conditions are as follows: 1.Normal operation of the pantograph network Condition 2.Catenary power supply voltage fluctuation condition 3.Train acceleration condition(3)Simulation research on electromagnetic compatibility environment of electrified trains:First,establish the electromagnetic compatibility theoretical model and three-dimensional simulation analysis model of electrified trains.According to the research results of the electromagnetic environment under the above three working conditions,numerically simulate the magnetic field environment at various points inside and outside the train,and obtain the electromagnetic field distribution characteristics of the electrified railway inside and outside the carriage.Secondly,we will study and analyze the external electromagnetic environment of electrified railways(such as 40 W communication base station with a frequency of 1900 MHz outside 1km,1MW monopulse radar with a transmission frequency of 10 GHz outside10km,etc.),and analyze the electromagnetic field distribution characteristics inside the train.Simulation analysis.