比例方向阀控气动缸动力机构建模

讨论了比例方向阀气动缸动力机械建模问题，采用工作点线性方法建立了动力机构和四阶模型，对位置系统和力系统推导了它的状态空间和传递函数形式，气缸两腔的压力动态存在差异，并且这个差异导致无法使用负载压降这个中间变量，基气动系统的这个特点，本文没有导出伺服系统的特性，并研究了平衡点附近系统模型参数的获取问题，为定量分析打下基础。

Modeling of pneumatic cylinder controlled by electronic

The model of a pneumatic actuator consists of an electronic proportional directional valve and a pneumatic cylinder. By linearization at operating point, some 4 th order models, which are different from often been used 3 rd order ones, include state space forms and transfer function forms, are derived for position control and force control respectively. The dynamic characteristics of pressures in the two chambers of a cylinder are different from each other, and the difference causes the variable of load pressure drop useless in the modeling of a pneumatic system. The variable of load pressure drop is therefore not adopted and models are derived directly from first order approximates of the pressure dynamic equations. The models correctly describe the characteristics of the pneumatic system. How to get the parameters of the models when the system is close to equilibrium is also discussed for the purpose of quantitative analysis.