适用于制动工况下的轮轨低黏着改进模型

Improved Model for Degraded Wheel-rail Adhesion under Braking Conditions

针对轨道车辆制动工况下的低黏着特性,分析防滑控制作用下制动力调节引起轮轨间黏着变化和改善的原因;基于滑动功率和滑动能对Polach黏着模型进行改进,并考虑各轴随位置不同的黏着修正,给出适用于制动工况下的轮轨低黏着模型;基于Matlab/Simulink和AMESim的联合仿真,进行紧急制动工况下的制动防滑控制仿真分析,并与试验数据进行对比,验证所改进低黏着模型的有效性和实用性;提出基于速度差的统计指标,可对制动防滑控制过程的仿真有效性进行评估。结果表明,改进的黏着模型符合规范BS EN 15595—2018的黏着曲线仿真要求,方法简洁,计算高效,涉及参数较少,更好地再现了制动工况下轮轨间的低黏着状态,且能够直接应用到列车制动过程中的防滑控制实时仿真。

In response to degraded adhesion characteristics of railway rolling-stock under braking conditions,an analysis was made on the causes of adhesion variation and improvement while braking forces were adjusted under the action of anti-skid control.Based on slip power and slip energy,an improved method for Polach adhesion model was developed.With consideration of adhesion correction along every axle position,a degraded adhesion model suitable for braking conditions was presented.The analysis was made on anti-skid control under emergency braking condition based on co-simulation of Matlab/Simulink and AMESim and the effectiveness and practicability of the improved model were validated by comparing the experimental data.According to velocity difference,statistical indexes were presented to evaluate the validity of the simulation of anti-skid during braking process.The results indicate that improved model meets the requirement for simulation of adhesion profiles in the BS EN 15595—2018 code.The improved adhesion model,simple,easy and efficient to use,better reproduces the low adhesion state between wheel and rail under braking condition and can be directly applied to the real-time anti-skid simulation for braking of railway vehicles.