Research and Application of Traction System for Urban Rail Transit Trains Virtual Marshalling

Objective To address the new requirements of virtual marshalling technology for train traction systems, such as high precision, rapid response, and safety reliability, a research on traction systems suitable for virtual marshalling trains is carried out, with its onboard application achieved. Method By investigating the characteristics and application scenarios of virtual marshalling technology, the functional requirements and technical indicators of the traction system are defined. A bogie-controlled technical solution for the traction system is proposed. Train performance simulation calculations are carried out in combination with specific line conditions to complete the development, ground testing and onboard validation of traction system products. During the debugging process, the simulation model is optimized and the control strategy is iterated through comparative analysis of experimental data and simulation results. Result ＆ Conclusion The traction cut-off delay during emergency braking is only 14 ms, far below the 200 ms design requirement, with the system passing SIL4 safety certification. The electric braking torque begins to decline linearly when speed drops to 3.1 km/h and approaches zero at 0.3 km/h, enabling smooth and precise stopping without impact. Under flat straight track conditions, the deviation between actual and simulated traction/braking acceleration values is controlled within ±5% after calibration, verifying the reliability of the model.