相较负载敏感系统，采用泵阀协同压力流量复合控制系统时流量控制更加精准，系统压损更小。但采用压力传感器检测阀口前后压差、实时调节阀口开度来实现流量精准调节，当阀口压力高频波动时会引起阀芯振荡，从而导致压力冲击和流量不稳定。针对这种情况，提出一种提高系统阻尼比的压差-位移检测装置，实现在压力高频波动时抑制阀芯振荡以提高系统稳定性。利用AMESim软件建立电子压力补偿的控制系统模型并验证；建立具有该装置的控制系统仿真模型，通过仿真研究该装置对系统特性的影响。结果表明：该装置中的弹簧刚度、黏性阻尼系数、活塞质量对系统特性的影响依次减小；当负载频率小于50 Hz时，不采用压差-位移检测装置可以保证流量的稳定以及准确;当负载频率为50~80 Hz时，采用压差-位移检测装置的输出流量的波动减小了15%~30%;主阀芯的振荡减小了约85%。
Compared with the load sensing system,the pump-valve coordination pressure and flow control system is adopted to achieve more accurate flow control and less system pressure loss.However,since the pressure sensor is used to detect the differential pressure before and after the valve port and adjust the valve port opening in real time to achieve accurate flow regulation,high-frequency fluctuation of valve port pressure will cause spool oscillation,resulting in pressure shock and flow instability.In view of this situation,a differential pressure-displacement detection device was proposed to improve the damping ratio of the system,which could suppress the spool oscillation when the pressure fluctuated at high frequency to improve the stability of the system.The control system model of the electronic pressure compensation was established and verified by AMESim.The control system simulation model with the differential pressure-displacement detection device was established,and the influence of the device on the system characteristics was studied through simulation.The results show that the effects of spring stiffness,viscous damping coefficient and piston mass on system characteristics decrease successively.When the load frequency is less than 50 Hz,the stability and accuracy of the flow can be ensured without the differential pressure-displacement detection device.When the load frequency is between 50 Hz and 80 Hz,the output flow fluctuation is reduced by 15% to 30% by using the differential pressure-displacement detection device,the oscillation of the main spool is reduced by about 85%.
ZHAO Dong, YANG Jing. Research on Characteristics of Multi-way Valve with Differential Pressure-Displacement Detection Device[J]. Machine Tool & Hydraulics,2023,51(20):17-25