Virtual Formation Train Tracking Control Strategy Based on Sliding Mode Control

Objective In existing train control systems based on moving blocking, there is a significant safety margin between adjacent trains. This leads to a mismatch between the transportation efficiency of a segment and its actual capacity needs, especially during peak passenger flow periods. Virtual formation trains can increase line capacity and better adapt to imbalanced commuter flows. Therefore, it is essential to develop a high-precision tracking control strategy suitable for virtual formation trains. Method To address the operational control challenges of virtual formation trains, a tracking control strategy based on sliding mode control is proposed. A train dynamics model and a virtual formation train operation control model are developed. A non-singular terminal sliding mode controller is designed, its performance is tested through simulations. Result & Conclusion Under the proposed virtual formation train control strategy, both the position and speed tracking errors of the virtual formation trains can asymptotically converge to zero along the sliding mode surface within a finite time. In the simulation verification tests involving four trains, when the operating state of the lead train changes, the other trains in the virtual formation quickly follow the expected speed trajectory, demonstrating the effectiveness of the proposed control strategy for virtual formation train tracking control.