Research Of Adhesion Control Method And Hardware-in-the-loop Simulation Based On HXD2 Heavyduty Locomotive

The moving of electric locomotive is relied on the wheel-rail adhesion which converts the power of motor to the tractive force.Adhesion utilization of wheel-rail plays an important part to ensure the stability and safety.The adhesion is strongly affected by the rail conditions such as water,oil.The tractive force is reduced significantly and unable to fulfill the actual traction demand when the wheel slip phenomenon occurs.Therefore,it is crucial to research effective adhesion control methods to improve adhesion utilization and ensure the stable traction force.The traditional method has a good control effect,but with the heavy-duty locomotive velocity and load increasing,the relevant adhesion performance still needs further optimization.Aiming at this problem,an optimized adhesion control method based on traditional is proposed in this thesis.First,a method achieving online search of optimal traction torque is proposed,which uses the wheel-set single axle model.Wheel slip phenomenon is detected by wheel slip velocity and wheel acceleration.The optimal traction torque under current rail condition is obtained based on adhesion coefficient-slip ratio relationship which is analyzed using O.Polach model.The method overcomes the problem that adhesion state far from the optimal point caused by repeated rise and fall of traction torque in traditional method.The optimized traction torque adjustment algorithm is discussed based on the wheel acceleration characteristic during the wheel re-adhesion process.The moving filter algorithm is developed,which changes point numbers according to the characteristic of slip detection and slip convergence detection.Those methods effectively avoid the traction torque excessive loss.Next,the whole locomotive model is as the research object.An adhesion method considering the axle traction control system is proposed.The impact of axle-load transfer to wheel-rail adhesion is discussed.Full-dimension state observer is designed to estimate the adhesion force which is used to calculate the detail axle-load transfer value among axles.The optimal traction torque matching the actual adhesion state of each axle is computed respectively.And by taking advantage of the axle traction control system,each axle can individually adjust the traction torque.Finally,considering the costly characteristic of actual testing,a simulation model is built based on Modeling Tech real-time simulator,which can efficiently test the accuracy and feasibility of the adhesion control method with low cost.The experimental results verify that the proposed methods effectively restrain the slip phenomenon,improve the adhesion utilization,and guarantee the actual traction force of locomotive.