气压伺服系统的建模与特性  

Modeling and characteristics of pneumatic servo system

作　　者：王燕波[1] 王祖温[1,2] 杨庆俊[1] 包钢[1] 

机构地区：[1]哈尔滨工业大学机电学院,哈尔滨150080 [2]大连海事大学机电与材料工程学院,辽宁大连116026

出　　处：《吉林大学学报（工学版）》2009年第5期1186-1191,共6页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家自然科学基金项目(50375034);211学科建设基金项目(CAAZ92102001)

摘　　要：研究了比例流量阀静态和动态特性。通过理论分析和实验研究,得出了临界压力比随阀开口面积呈先增大后减小的非线性规律变化,其值在0.17到0.38之间。通过实验研究,计算出流量系数随阀开口面积呈非线性变化的规律,其值在0.55到0.77之间。采用正弦扫频激励信号和直接测量阀芯位移方法得出了阀的频率特性,随着输入信号幅值的增大,阀的带宽减小,而供气压力改变对阀带宽几乎没有影响。采用集中参数模型描述了气缸内气体与气缸壁以及气缸壁与外界的传热过程,推导出气体温度微分方程,建立了气缸内气体热力学模型。最后,进行了仿真和实验研究,仿真数据与实验数据吻合得较好。The static and dynamic characteristics of the pneumatic proportional flow-rate control valve were studied. It was found that the variation of the critical pressure ratio versus the valve opening is non-linear, it increases at first and then decreases, and the ratio ranges from 0. 17 to 0. 38. The discharge coefficient was calculated with the help of Sanville flow formula by measuring the flow-rate through the valve at different openings, and the coefficient ranges from 0.55 to 0.77. The relationship between the discharge coefficient and the valve opening was found non linear also. The frequency response of the valve was acquired by the sine sweep exitation and the spool position measurement. The results show that the bandwidth of the valve decreases with the increase of the input signal amplitude, and the supply gas pressure has no effect on its bandwidth. The heat transfer processes between gas in the cylinder and the cylinder wall, as well as between the cylinder wall and the environment were described using a lumped parameter mathematical model. A differential equation of the gas temperature was deduced and a thermodynamic model of in-cylinder gas was established. The simulation and experiment of the pneumatic servo system were performed and the simulation results agree well with the experiment ones.

关 键 词：传动与控制 气压伺服系统 建模 比例流量阀 热力学过程 

分 类 号：TH137[机械工程—机械制造及自动化]