Hardware Design Of Dynamic Simulation Experiment System For Urban Rail Transit

Nowadays,the development of urban rail transit has gradually alleviated the problem of traffic inconvenience caused by the significant increase in urban population.This subject establishes a low-power full-materialized rail transit traction power supply simulation platform to simulate the operating conditions and fault conditions of the actual traction power supply system.This is of great help to the research on the operational safety of urban rail transit and new technologies.This paper investigates the development process and research status of traction power supply dynamic simulation system for urban rail transit at home and abroad.Combined with the requirements of traction power supply simulation platform for urban rail transit,the overall layout and structural design scheme of the dynamic simulation system platform are proposed.According to the design principle of equal scale and adjustable parameters,the main substation,power supply system and power supply system are completed Traction substation and the main line of the train components selection and wiring diagram drawing design.Based on the functional requirements of the platform of urban rail transit dynamic simulation system,the core controlled object of the PWM rectifier in the dynamic simulation system is studied.By establishing the mathematical model of the dq rotating coordinate system and the small signal linearization mathematical model,a mathematical model is proposed.A double closed-loop control strategy of PWM rectifier.Based on the above-mentioned control and circuit parameter design results,a Matlab simulation model is built,and simulation experiments are carried out by simulating different train conditions to observe the DC voltage changes and the current waveforms of the on-board PWM rectifier and the PWM rectifier of the energy-fed unit to verify the reliability of the control strategy.Through the hardware design requirements and specific functions of the underlying control system,the TMS320F28377 s model DSP chip and the 10M02SCU169 model CPLD chip are selected as the main control chip,and the core control board based on the DSP+CPLD hardware structure is designed,and the core control board is designed The main station,each traction station and the power supply board cards of the train group constitute the hardware part of the bottom control system.The underlying control system integrates functions such as serial communication,Ethernet communication,relay control,contactor feedback,sampling detection,pulse width modulation,DC motor speed regulation,and circuit hardware protection.In terms of the software development of the underlying control system,according to the functions of the underlying hardware system,the programming of the underlying control system software based on Code Composer Studio software and Quartus software has been completed.The research in this subject is a new type of energy-fed traction power supply system.By controlling the four-quadrant PWM rectifier in the traction substation’s energy-fed unit and the train on-board converter,it can switch between rectification and inverter conditions.State to simulate the energy flow of the traction power supply system under various working conditions(traction,inertia,braking).By formulating the communication protocol with the upper-level interface monitoring system and the virtual oscilloscope,the two-way data transmission with the upper-level interface monitoring system has been realized,and the start-up of multiple stations and the start-stop of the on-board DC motor,forward and reverse control,and variable speed regulation have been completed.The virtual oscilloscope will be used to display the waveforms of various electrical quantities and train operating conditions in real time.In order to improve the stability and safety of the system operation,it is classified according to different fault levels,and the protection sequence is designed according to the occurrence of the corresponding fault type,which improves the system Overall stability.Finally,after experimental debugging,the software and hardware of the bottom-level control system of the designed dynamic simulation system platform are tested as a whole to verify the rationality and feasibility of the bottom-level control system design.Through the joint debugging of software and hardware,the support experiment of the energy feed station and the on-board converter module of the train group is completed,and the energy flow of the traction power supply system under various working conditions(traction,inertia,braking)is simulated.This article has a total of 69 figures,3 tables,and 48 references.