Abstract:
Objective The accuracy of train stopping under ATO (automatic train operation) mode in urban rail transit is a comprehensive issue. To improve the accuracy of train stopping at stations, it is necessary to jointly analyze train undershooting at stop points from the disciplines of vehicle traction, braking, and signaling systems, and propose corresponding improvement strategies.
Method Based on the control logic of the station train stopping process on Luoyang Rail Transit Line 1 (hereinafter referred to as ′Line 1′), the causes for train undershooting are analyzed from four aspects: train braking system, ATO mode, wheel slide protection system, and external environment. Based on the train coasting trigger logic and compensation mechanism, improvement strategies are proposed in terms of ATO system parameter optimization, wheel flange lubrication device control, tunnel ventilation system operation, and optimization of train braking system parameters.
Result & Conclusion The improvement strategies for train undershooting at stop points on Line 1 are as following: by collecting coasting signals from motor cars and trailer cars, the signaling system may optimize and adjust ATO system parameters, thereby improving the adaptability of ATO system and enhancing stopping accuracy; according to the characteristics of Luoyang′s winter climate, line conditions, and the layout of rail lubrication devices, the maintenance personnel should adjust the oil spraying duration of wheel flange lubrication devices and shut off some train lubrication devices to reduce the use of flange lubricant on mainline tracks; by collecting and analyzing temperature and humidity data in station intervals, relevant departments of the operation company should be engaged to explore optimization of tunnel ventilation strategies to improve the train operation environment. Finally, if train stopping accuracy shows large dispersion caused by excessive pneumatic braking force during the electro-pneumatic conversion, the pneumatic braking force should be appropriately reduced. Under opposite circumstances, ATO system parameters should be adjusted to improve the adaptability of the ATO system and further enhance stopping accuracy.