液压驱动车辆反拖工况下的发动机转速稳定性研究

Research on engine speed stability of hydraulic driving vehicles in dragged condition

为研究液压驱动车辆发动机转速稳定性的优化控制问题,针对现行液压驱动车辆在急减速以及下坡道时,由于车辆惯性大使得发动机被反拖而导致的失速问题,提出主动增加发动机的摩擦力矩和串接辅助泵的解决方案;以液压驱动某型钢轨打磨车为例,对系统进行数学建模,分析反拖工况下发动机的失速机理,研究车辆反拖工况时发动机摩擦力矩与转速的关系;采用AMESim对系统进行仿真,对发动机在反拖工况下的转速稳定性进行优化控制;研究结果表明:通过主动增大发动机的转速来提高摩擦力矩以及串接辅助泵等方案均能有效地解决发动机的反拖失速问题,提高了车辆运行的平稳性和安全性。

The paper devotes to research on the optimal control problem of hydraulic driving vehicle engine speed stability.In order to solve the problem of the stall of the engine caused by the vehicle inertia ambassador,when hydraulic driving vehicle was in emergency deceleration or working on the down ramp,the initiative to increase the friction torque of engine and the auxiliary pump solutions were put forward.Taking the hydraulic driving rail grinding train for example,the mathematical model was established,and analysis of the mechanism of stall was performed,by which the relationship between vehicle engine friction torque and speed of the dragged condition was researched.The simulation of the system was carried out with the AMESim,and the optimal control of speed stability was obtained under dragged conditions of engine.The results show that it is an effective solution to solve the engine dragged stall problem by increasing the friction torque and joining -up of auxiliary brake pump through active increase of engine speed,and it could improve the stability and the safety of vehicle operation.