The Dynamic Study On The Active Radial Bogie Of The Tilting Trains

Tilting train can go through the curve sections in the high speed without changing the ride comfort of the passengers, is one of the most effective and economical choices for increasing speed of exiting track in the world. However, going through the curve sections in the high speed, which resulted in the increase of the wheel/rail contact force and wheel/rail wear, and using the traditional bogie is bound to reduce the running safety, therefore the concept of the radial bogie was put forward. The wheel/rail wear can be reduced effectively with using the radial bogie and the radial bogie has the better curve negotiation performance, so the radial bogie has been widely used in tilting trains. The active radial bogie is one kind of the radial bogie, compared to the traditional radial bogies, the active radial bogie contains active radial control system and the active radial control mechanism. The active radial bogie can control the yaw movement of the wheelset based on the real-time information of the curve, making the wheelset in the radial position on the curve, and the hunting stability on straight track is enhanced. Active control technology is more and more widely applied in the field of railway vehicle, the active radial bogie will be get the attention of the experts and scholars of the railway vehicles in the world.Firstly, this paper introduces the basic principles of the active radial bogie and confirms the radial structure of the active radial control mechanism:Between the frame and the wheelset, the establishment of four actuators, respectively, control the the yaw movement of the wheelsets of the track, making the wheelsets in the radial position on the curve. The control law of the the active radial bogie is determined. Some structures of the tilting train are processed before modeling, and then the model is established in SIMPACK. The dynamic functions for each rigid body of the tilting train are made.Secondly, the control method of the control system of the tilting train is determined. Through comparative analysis of the classical PID control method, the fuzzy control method and the mixed fuzzy-PID control method shows that:The step response of the classical PID control method is faster, but the output of the control system is unstable; The output of the control system of the fuzzy control method is stable, but the step response the step response is relatively slow; The step response of the mixed fuzzy-PID control method is faster, and the output of the control system is stable. So the mixed fuzzy-PID control method is chosen.Finally, the dynamics performance of the tilting train is analyzed. The research contents include the lateral stability and response on the tangent track and curve negotiation of the tilting train. The comparative analysis of the curve negotiation of the conventional bogie, the self-steering bogie and the active radial bogie are done based on the dynamic evaluation index. The analysis shows that the active radial bogie can effectively reduce wheel/rail wear, the wheel/rail lateral force, derailment coefficient and wheel unloading rate. Compared to the self-steering bogie, the active radial bogie has better radial performance.