大功率拖拉机电液提升器比例提升阀设计

Design of Proportional Raise Valve in Electro-hydraulic Lifting Mechanism of Big-power Tractor

针对大功率拖拉机电液提升器,设计了比例提升阀,对4种不同型式节流口的流量特性进行了对比。基于状态空间法,建立比例提升阀的动态数学模型及仿真模型,在Matlab/Simulink中进行仿真及参数优化设计,并进行了室内试验。结果表明,采用半圆形节流口的阀芯行程短且具有良好的小流量特性;经参数优化之后,比例提升阀控制电流与流量曲线线性度决定系数为0.998 6,动态阶跃响应超调量为6.25%,调整时间为0.3 s。

A proportional raise valve was designed to meet the requirement of electro-hydraulic rockshaft on bigpower tractors. The flow rate characteristics of four types of regulator orifice were analyzed. The mathematical model of the valve was established based on state space method, then the stable performance and dynamic performance of the valve were simulated by using Matlab/Simulink. An indoor test-bed was built to test the designed proportional raise valve. The results showed that the valve core with half-round regulator orifice had shorter travel and better low-flow rate characteristics. The coefficient of determination of the linearity of flow rate curve due to the control current change was 0. 998 6. The overshoot of step response was 6.25% and the set up time was 0.3 s.