铰接车辆转向系统液压管路动态特性

摘要

对于铰接车辆转向系统,管路特性对转向系统性能影响较大,其影响因素不能被忽略.基于功率键合图-方块图方法及SIMULINK控制仿真软件,建立了铰接车辆转向系统液压管路至油缸及负载的通用数学模型.定量地研究分析了铰接车辆转向系统液压管路的动态特性以及液压管路参数对转向系统动态特性的影响.研究结果表明:对于小管径管路,液阻和液感较大,液容较小,系统振荡幅度小,响应速度快;随着管路长度的增加,液阻、液感和液容皆逐渐增大,系统振荡次数逐渐减少,振荡幅度逐渐减小,但是系统动态响应较慢;提高油液的等效体积弹性模量有利于改善系统的动态响应速度和稳定性.%For articulated vehicles steering system, the pipelines characteristics have great effects on the steering system performance, the impacts can not be ignored. Based on power bond graph-block diagram method and SIMULINK software, the general mathematical model of the hydraulic pipelines to the load of the articulated vehicles steering system was established. The dynamic characteristics of hydraulic pipelines of the articulated vehicles and the influence of the pipelines parameters on the articulated vehicles steering system were analyzed quantitatively. The study results show that for smaller diameter pipelines, the fluid resistance and fluid sense get larger, the fluid capacity gets smaller instead. The system oscillation amplitude is smaller and the dynamic response is faster; with an increase in the length of pipelines, the fluid sense, fluid resistance and fluid capacity are all increasing gradually, the system oscillation frequency reduces gradually, the oscillation amplitude also gradually decreases, but the dynamic response is getting slower. Increasing the oil volume elastic modulus of the system is conducive to improve the dynamic response speed and stability.