气动薄膜执行机构模型优化及参数辨识  

Model Optimization and Parameter Identification of Pneumatic Membrane Actuators

作　　者：金纵横 李世伟 尚群立[1] JIN Zongheng;LI Shiwei;SHANG Qunli(School of Information Engineering,Zhejiang University of Technology,Hangzhou 310023,China)

机构地区：[1]浙江工业大学信息工程学院,杭州310023

出　　处：《计算机测量与控制》2023年第9期213-219,共7页Computer Measurement &Control

基　　金：国家科技重大专项项目(2018ZX06005002)。

摘　　要：在气动调节阀中,针对智能电气阀门定位器控制算法的开发通常需以气动薄膜执行机构模型为基础;本研究对应用于气动薄膜执行机构的传统Karnopp摩擦模型进行了优化,对动静摩擦判断条件DV(临界速度)进行修改,修改后的模型解决了DV如何选取这一问题;同时对传统气动薄膜执行机构模型的参数辨识方法进行改进,将多元线性回归和最小二乘法应用于估算气动薄膜执行机构中移动部件质量,弹簧刚度系数,预紧力,库伦摩擦和粘滞摩擦系数,通过实际气室压力和估计气室压力的标准误差σ、相关系数R^(2)与参数向量α中每个参数对应的p-value三个指标来决定参数的选取结果;将摩擦模型整合进气动薄膜执行机构动力学模型中,通过仿真和实验验证了参数辨识方法有效性;在开环不同幅值的阶跃信号和随机信号激励下进行仿真和实验对比,结果表明,整合后的摩擦模型能准确模拟气动薄膜执行机构的动态过程,该模型和参数辨识方法同样适用于其它机械装备。In pneumatic control valves,the development of control algorithms for intelligent electrical valve positioners usually needs to be based on the pneumatic membrane actuator model;In this paper,traditional Karnopp friction model is applied to optimize pneumatic membrane actuators,and modify the dynamic and static friction judgment condition critical speed(DV),the modified model is used to solve how to select the problem of the DV.The parameter identification method of traditional pneumatic membrane actuator model is improved,and the multiple linear regression and least squares method are applied to estimate the mass of moving parts,spring stiffness coefficient,preload force,Coulomb friction and viscous friction coefficient in the pneumatic membrane actuator,and the parameter selection result is determined by the actual air chamber pressure and the standard errorσof the estimated air chamber pressure,the correlation coefficient R^(2)and the p-value corresponding to each parameter in the parameter vectorα.The friction model is integrated into the dynamic model of the pneumatic thin film actuator,and the effectiveness of the parameter identification method is verified by the simulation and experiment.The simulation and experimental comparison are carried out under the stimulus of step signals and random signals with different amplitudes in the open-loop,the results show that the integrated friction model can accurately simulate the dynamic process of the pneumatic membrane actuator,the model and parameter identification method are also applicable to other mechanical equipment.

关 键 词：气动薄膜执行机构 Karnopp摩擦模型 多元线性回归 最小二乘法 参数辨识 

分 类 号：TP214[自动化与计算机技术—检测技术与自动化装置]