Adhesion Control of Heavy-Duty Locomotive Based on Axle Traction Control System

The traction force of heavy-duty locomotive is reduced significantly and unable to fulfill the actual traction demand when the wheel slip phenomenon occurs. Aiming at this problem, an adhesion control method is proposed in this paper. The proposed method achieves online search of optimal traction torque based on adhesion coefficient-slip ratio relationship which is analyzed using Polach model. The optimal traction torque is the maximum torque which is operating under current wheel-rail condition without slip phenomenon. The proposed method detects wheel slip phenomenon by wheel slip velocity and wheel acceleration. Each axle in locomotive achieves individual traction torque adjustment by utilizing the advantage of axle control system. Considering the complexity of real heavy-duty locomotive, a co-simulation model is proposed by using MATLAB/Simulink to build the electric power circuit and control system as well as SIMPACK to build the locomotive mechanical system. The simulation is realized based on the StarSim real-time simulator platform and the experimental results verify the effectiveness of the proposed method.