地铁列车空气制动系统仿真模型

Simulation model of air braking system for subway train

分析了地铁列车空气制动系统工作原理与构成,研究了容性、阻性和感性单元三类基本气动元件建模原理,根据相似性原理,通过AMESim软件建立了地铁列车空气制动系统仿真模型,介绍了空重车阀、EP单元、中继阀等部件建模过程,并对仿真参数进行了分析。研究了常用制动、紧急制动和阶段制动工况下制动缸压力与Cv压力变化特性,并进行了试验台对比验证。分析结果表明:在常用、紧急制动时,Cv压力比制动缸压力响应快,最大延时不超过0.5s,稳定时两者压力相等;紧急制动时制动缸压力上升至定压的时间小于1.5s,常用制动时小于2.2s;阶段制动时制动缸压力与Cv压力跟随性较好。试验中制动稳定后Cv压力比制动缸压力高约15kPa,由中继阀内部橡胶件阻尼作用引起,该误差不影响中断阀正常使用。

The structure and operating principle of air braking system for subway train were introduced.The modelling methods of three basic types of pneumatic components including capacitive,resistive and inductive unit were explained.The simulation model of air braking system was built based on the similarity principle and the AMESim.The models and simulation parameters of load valve,EP unit and relay valve were analyzed.The characteristics of brake cylinder and Cv pressures were discussed under service brake,emergency brake and phased brake,and the result was verified by test bench.Analysis result shows that Cv pressure response is faster than the pressure response of brake cylinder in service and emergency brake,the maximum delay is no more than 0.5 s,and the stabilities of both pressures are equal.It takes less than 1.5 s when brake cylinder pressure rises to the constant pressure in emergency brake,and the value is less than 2.2 s in service brake.Regarding phased brake,brake cylinder pressure and Cv pressure follow better.In test,stabile Cv pressure is about 15 kPa higher than brake cylinder pressure because of the damping effect of internal rubber parts of relay valve,but the error does not affect the normal use of relay valve.