基于模糊PID的电液比例阀流量控制设计及分析

Flow control design and analysis of electro-hydraulic proportional valve based on fuzzy PID

为了提高对电液比例阀的控制精度,设计了一种新型模糊PID位置控制器。通过液力传感器测试先导阀口压差,实现对先导阀芯位移的快速校正,再利用主阀完成功率流量的线性放大。以主阀位移期望值的偏差和偏差变化率,将此两个因素作为输入,对比例阀位移进行控制修正,并对比例阀模糊PID位置控制器进行AMESim-Simulink联合仿真。研究结果表明:输入阶跃信号响应后,先导进液阀芯发生响应,响应时间总共为102 ms,调整后时间缩短了115 ms,误差降低0.12 mm,主阀芯完成了稳定的动作过程,最终获得了284.2 L·min^(-1)的稳定输出流量。在比例斜坡响应时,先导进液阀出现超调,此时主进液阀芯跟随控制信号动作,使误差降低到0.14,大幅降低了系统振荡幅度。以上研究结果表明,本文设计的模糊PID控制方法是有效的。

In order to improve the control accuracy of electro-hydraulic proportional valve,a new fuzzy PID position controller is designed.The hydraulic sensor is used to test the differential pressure of the pilot valve port to achieve the rapid correction of the pilot spool displacement,and then the main valve is used to complete the linear amplification of power flow.Taking the main valve displacement,expected value deviation and deviation change rate as input,the proportional valve displacement is controlled and corrected,and the AMESim-Simulink co-simulation is carried out for the fuzzy PID position controller of the proportional valve.The results show that:after the step signal response,the pilot inlet valve spore responds,and the response time is 102 ms in total.After adjustment,the time is shortened by 115 ms,and the error is reduced by 0.12 mm.The main valve spore completes the stable operation process,and finally achieves a stable output flow rate of284.2 L·min^(-1).When the proportional slope response occurs,the pilot inlet valve overshoots.At this time,the main inlet valve spool follows the control signal,reducing the error to 0.14 and greatly reducing the oscillation amplitude of the system.The results above show that the fuzzy PID control method designed in this paper is effective.