多路阀可视化机液系统建模及动态特性

为研究LBF20型电液比例负载敏感多路阀的动态特性及参数优化,分析了此多路阀的工作原理及流量共享分配特性,提出了用AMEsim软件建立基于挖掘机的可视化机液一体化系统模型的新方法.再将铲斗动臂收缩复合动作时系统流量分配特性的仿真结果与理论分析对比,验证系统模型的正确性.采用批参数运行和控制变量的方法,研究了三通流量补偿阀的弹簧预压力、LS管路的直径、长度和横截面形状对系统动态特性的影响,确定最佳参数范围.结果表明:三通流量补偿阀的弹簧预压力设定在150~350 N较合理,且预压力增大,进入负载联的流量、压力裕度和泵出口压力均增加;LS管径适当增大,管内流体为层流,管路上的压降几乎为0,此时管路长度和横截面形状对系统特性影响较小.建模方法可为其他多控制阀机液系统建模提供参考,LBF20型多路阀系统模型可用于其进一步的参数优化和动态特性研究.

Modeling and dynamic characteristics of multi-valve visualization machine-liquid system

To analyze the dynamic characteristics and optimize the parameter of LBF20 electro-hydraulic proportional load sensitive multi-way valve,the control principle and the flow distribution characte-ristics of this valve were analyzed. A new method for constructing a visualized machine-liquid integrated system model based on excavator with AMEsim software was proposed. To verify the correctness of the model, the distribution characteristics of flow were compared from simulation results and theoretical analysis. The effect of the spring pre-pressure of three-way flow valve,the diameter,the length and the cross-sectional shape of LS pipe on the dynamic characteristics of the system was stu-died by batch operation and control variables. The results show that the spring pre-pressure of the three-way flow valve should be set at 150-350 N.With the pre-pressure increasing, the flow rate entering the load, the pressure margin and the pump outlet pressure are increasing. When the diameter of LS pipe increases appropriately, the state of fluid is laminar, so the length and cross-sectional shape of the pipeline have little influence on the system. The modeling method can provide a reference for other multi-control valve system modeling, and the LBF20 multi-way valve model can be used for the further parameter optimization and dynamic characteristics research.