货车极限黏着制动优化方法

Braking optimization method of wagon under limit adhesion

基于Polach大纵向蠕滑理论的轮轨接触模型,确定了铁道车辆在制动工况下,轮轨黏着系数达到饱和时的轮轨蠕滑率。以闸瓦压力为优化对象,以轮轨蠕滑率为目标函数,在SIMPACK环境下构建了考虑制动系统的车辆动力学模型。通过ARX系统辨识技术,在SIMULINK环境下构建了轮轨蠕滑率响应的参照系统。为了使车辆模型与参照模型的蠕滑率在制动过程中保持一致,基于MIT自适应控制技术对制动时车辆的蠕滑率响应进行了跟踪,以实现对闸瓦压力施加方案的优化。计算结果表明:与一般闸瓦压力施加方案比较,优化后的闸瓦压力使轮轨最大蠕滑率下降了71.6%,使制动结束时的车速下降了11.8%,说明优化后的闸瓦压力不但能有效避免轮轨间的擦伤,还能够在一定程度上缩短车辆的制动距离。

Based on the wheel/rail contact model of Polach＇s large creep theory, the creepage corresponding the saturated adhesion coefficient was determined in the brake condition of wagon. As block pressure was taken as the optimization objective and the creepage was taken as the objective function, vehicle dynamics model was built in SIMPACK environment under considering braking system. By ARX system identification, the reference system of creepage response was modelled in SIMULINK environment. On the purpose that the creepages of MBS model and reference model kept consistent during the brake, the creepage response was tracked by using MIT adaptive control technic, and an optimized method to apply block pressure was obtained. Compared with other ordinary methods, the optimized method decreases 71.6% of the maximal creepage and 11.8% of vehicle velocity at braking end, which can effectively eliminate wheel/rail slide and shorten the brake distance to a certain extent. 1 tab, 9 figs, 13 refs.