电液伺服增压系统压力冲击抑制方法研究

Research on Pressure Shock Suppression Method for Electro-Hydraulic Servo Booster System

传统阀控增压系统通过开环控制换向阀来控制双作用增压缸高频次往复运动进而达到高压容腔的工作压力,但开环控制换向阀频繁阶跃换向会导致巨大的压力冲击,易造成系统元件损坏与管路破裂等问题,影响系统稳定性和可靠性。因此,基于增压缸位置闭环与主动调节液压泵输出压力的复合控制策略连续调节换向阀的阀芯位移,从而减小增压缸系统工作过程中液压冲击。利用多学科仿真软件SimulationX搭建所提增压系统液压仿真模型,与传统阀控增压系统试验所得曲线对比。结果表明:所提系统增压缸油腔刚启动时压力冲击由19.45 MPa降低为7 MPa,运行过程中增压缸油腔压力冲击由4.8 MPa降低为1.11 MPa,液压泵压力冲击由18.3 MPa降低为2.8 MPa。此方法可有效降低增压系统压力冲击,具有良好的减缓冲击效果,有助于增强系统可靠性,延长元件及系统寿命,降低运维成本。

The traditional valve controlled booster system controls the high-frequency reciprocating motion of the double acting booster cylinder through an open-loop control directional valve to achieve the working pressure of the high-pressure chamber.However,frequent step reversing of open-loop control directional valves can cause huge pressure shocks,which can easily cause problems such as system component damage and pipeline rupture,affecting system stability and reliability.Therefore,a composite control strategy based on closed-loop position control of the booster cylinder and active adjustment of the output pressure of the hydraulic pump continuously was proposed to adjust the displacement of the valve core of the directional valve,thereby reducing hydraulic impact during the operation of the booster cylinder system.A hydraulic simulation model of the proposed booster system was built using multidisciplinary simulation software SimulationX,and the simulation results were compared with the curves obtained from traditional valve controlled booster system experiments.The results show that the pressure shock of the proposed system′s booster cylinder oil chamber decreases from 19.45 MPa to 7 MPa when it is first started,and during operation,the pressure shock of the booster cylinder oil chamber decreases from 4.8 MPa to 1.11 MPa,while the pressure shock of the hydraulic pump decreases from 18.3 MPa to 2.8 MPa.This method can effectively reduce the pressure impact of the booster system,has a good impact mitigation effect,helps to enhance system reliability,extend the lifespan of components and systems,reduce operation and maintenance costs.