Integrated sliding mode and direct torque controls for improving transient traction in high-speed trains

Wheel slip control in high-speed trains is used to reduce the acceleration time and produce the maximum traction motor power. For controlling slip in a complete model of a train consisting of the traction motors, it is needed to keep the adhesion coefficient as much as possible by controlling the input voltage. In this article, integrated sliding mode and direct torque controls are used to control the transient traction in a full model of a high-speed railcar consisting of a wagon, two bogies, four wheelsets, and four traction motors. Cosimulations in SIMPACK with MATLAB/Simulink are carried out to evaluate the performance of the designed control structure. By comparing the results of the open-loop and closed-loop simulations, it is shown the acceleration time of the high-speed railcar is decreased 26% and the production of the traction motor power is increased 32% for both dry and wet surface conditions. It is also shown that the designed control structure is stable and robust in the presence of uncertainties.