Simulation Research On APM Traction Power Supply System

Automated People Mover(APM)is a kind of rail transit system with medium and low traffic volume,fast shuttle transportation and fully automatic driverless.It has been widely used in many large-scale hub airports abroad,and APM routes of domestic airports are basically in planning,reserving or under construction.Traction power supply system is an important part of APM project.The safety and reliability of power supply quality will directly affect the normal operation of the system.According to the specific line characteristics,it is very important to compare and select the appropriate power supply scheme before the new APM line is built to save the overall investment of the project and improve the quality of power supply.Different from urban rail and electrified railway,APM system has two power supply modes:three-phase AC system and DC system.And the applicable distance,complexity and power quality of different power supply systems have their own advantages and disadvantages.At present,there is still a lack of effective power supply scheme optimization methods.Therefore,based on the traditional comprehensive evaluation theory,this thesis studies and establishes a set of auxiliary decision-making system suitable for APM system power supply scheme.Firstly,the basic structure of APM power supply system is summarized.The power supply mode of high voltage power supply system and the composition of power lighting system are briefly introduced.The advantages and disadvantages of different power supply modes for traction power supply system are analyzed emphatically.In addition,the principle of setting up the traction substation,types and operation modes of traction network are introduced.Secondly,based on the full understanding of the working principle of each component of the system,the simulation models of three-phase AC and DC traction power supply system are built by using Simulink software.It mainly includes four parts:external power supply,traction substation,contact rail and vehicle system.Then,taking APM system of Guangzhou Pearl River New Town as an example,three power supply schemes are proposed according to its line characteristics.The voltage distribution on the contact rail and the traction motor state of the system in single train operation,multi-train operation and the faulty exit operation of traction substation are simulated and analyzed.The results show that the variation of contact rail voltage in each scheme is consistent with the actual situation and meets the permissible fluctuation requirements of the transmission line.The motor speed can be stabilized at the rated value during normal operation of the system,which verifies the reliability and safety of the design scheme.Finally,the combination of fuzzy comprehensive evaluation and analytic hierarchy process is used to optimize the designed power supply scheme.In terms of technology and economy,seven evaluation indexes are determined.According to the characteristics of three-phase AC and DC power supply modes,the weight of each index and the corresponding membership degree are calculated,and the better power supply scheme is obtained.It provides a scientific basis for the selection of traction power supply scheme for the new APM systems in the future.