基于Simulink的气控液压背压阀仿真与设计

Pneumatic Control Hydraulic Back Pressure Valve Simulation and Design Based on Simulink

在Simulink中建立了气控液压背压阀的仿真模型并对其进行设计,目的在于实现根据气路压力控制液压回路背压的功能,使其能够连结气动与液压控制,在航空航天、能源、动力等领域具有相当的应用空间和价值。在设计过程中采用的控制方法是对背压进行双闭环控制,其中外环利用PID控制调节液压回路背压,内环通过控制无刷直流电动机来调节针阀阀芯位移,并且利用Simulink仿真确定不同给定量对应的PID控制器参数。单片机作为背压阀控制系统的核心,依据各个传感器采集的信号选择PID控制器参数,进而调节电动机转速,实现背压的精确控制。通过测试可以得出结论,该背压阀达到了设计目标,解决了非线性系统的PID控制问题,在气压不同时能够稳定、准确、快速地调节液压回路背压。

This article founds the simulation model of the pneumatic control hydraulic back pressure valve in Simulink while designing this valve. The purpose is to realize the function of controlling the hydraulic circuit back pressure according to the pneumatic pressure, so that the hydraulic and pneumatic controls are combined to make this valve have relative applicant space and value in aviation, aero- space, energy and power, etc. The method resort in the designing process is controlling the back pressure with double closed loops in which the outside loop regulates back pressure with the use of PID control and the inside one regulates the displacement of needle valve cone through controlling the BLDM. Furthermore, the parameters of PID controller are determined by the Simulink simulation. As the core of the back pressure control system, the MCU selects the PID control parameters based on the signal collected to regulate the speed of the BLDM and realize the accurate control of back pressure. Through the test, the conclusion that this back pressure valve is able to reach the design purpose and to tackle the PID control problem of nonlinear system can be obtained. Under the different conditions of pneumatic pressure, this valve can regulate the hydraulic back pressure stably, accurately and rapidly.