Dynamic Performance Simulation Of High Speed Trains During Traction And Braking

Now high speed passenger dedicated lines such as Jing-Hu, Jing-Guang, Ha-Da and Zheng-Xi, etc., have gone into operation, and the highest running speed is300km/h. As the train speed increases, the influence of cross wind and track excitation on high speed train dynamic performance increases. Through building the dynamic model of the high speed train, the dynamic performance of the train in traction and braking is analyzed by considering different cross winds and track excitations.Firstly, the dynamic model of a high speed train with train formation6M2T is established, and the front car and rear car are trailer cars. According to the aerodynamic performance of the train under cross wind, the cross wind effect is simplified as concentrated forces and torques and exerted on the carboy. The basic running resistance of the train is loaded on each car as the function of speed. The traction torque on each wheelset is calculated according to the traction calculation formula. The braking force is determined by the wheel/rail adhesion force under different operating condistions.Secondly, the adhesion control model is set up by considering the effect of cross wind on the adhesion force of the high speed train. The creep velocity is taken as the control variable and adhesion utilization in traction and braking is controlled through changing the traction and braking toques.Finally, the average start acceleration, braking distance, creep velocity, traction and braking forces are studied for the high speed trains under different cross winds and track excitations. The dynamic performance is calculated under different condition, and the running safety and wheel wear index are investigated. The result shows that, the cross wind has significant influence on the traction dynamic performance compared with the effect of the track excitation. Then, the operating safety margin of the high speed train under cross wind is suggested.