Influences Of Suspension System Parameters On The Dynamic Performance Of High-Speed Trailer

With the improvement of train speed, the problems of comfort and safety become increasingly concerned, and the vehicle suspension system is a key factor affecting dynamic performance.Since the suspension systems are considered as the main way for passing force and motion between tracks and vehicles, their changed parameters will directly affect the size of force and motion passed and the form of body vibration, in order to help designers better understand the effect of vehicle suspension system on obtaining better dynamic performances of the vehicle, this article has studied parameters of springs and dampers in the primary and secondary suspension system to better understand the vehicle’s riding quality, curving safety, hunting stability.This article systematic analysis the effect of suspension parameters on the dynamic performance of vehicle systems, including the primary axle positioning stiffness,the primary vertical springs and vertical dampers, the secondary air springs, lateral and vertical dampers,anti-hunting dampers. The primary axle positioning stiffness has a great influenced on curving safety and hunting stability,the primary and secondsry springs play a supportive role, besides, they also has effect of damping vibration. For the riding quality of the vehicle what plays a major role are the primary and secondary vertical dampers, the damping value and the index of riding quality have non-linear relationship, values must be reasonable in order to obtain better stability properties.Air spring as a very effective damping component, not only has a smaller stiffness, but also provides greater vertical damping, and it has a drastic change in the horizontal position, its good damping performance now makes high EMU and urban rail vehicles which need good comfort are commonly used air springs. Therefore, this paper focuses on analysis of factors impacting on the damping performance of air spring, by studying this paper found that the bellow volume of air springs, additional volume, diameter of feed pipe affecting the damping performance are major factors. In addition, because a single air spring failure would cause a serious deterioration in the vehicle horizontal, vertical stability, so it is necessaryto ensure a longer life of air springs and better security,and the redundant design must be prepared to avoid the ride comfort getting down too much after the air spring is invalid. This article also analyzes the damper and air spring which are easily getting invalid, in order to find out the change of dynamic performances after they are invalid.and finally to be more clear how great a role suspension system play in improving vehicle dynamic performance. The critical speed of the vehicle will decrease after the failure of the unilateral bogie shock absorber, in order to prevent all the unilateral bogie yaw damper failure, there must be redundant design. After the failure of the air spring, the carbody contacts with bogie directly, the rail excitation pass from bogie to carbody without being debilitated by the secondary suspension, this will lead to bad riding quality. With the high driving speeds, the effect of horizontal and vertical damper on riding quality will be larger, in today’s increasingly high travel comfort requirements, trying to improve vehicle ride comfort has become more and more important, therefore,the horizontal and vertical damper are playing a great role.