基于传递函数的数字液压缸建模与分析

在考虑功率匹配和非对称结构特性的基础上，以液压弹簧刚度最小位置为工作点，推导了阀控非对称缸的传递函数，给出了合理的液压固有频率计算公式，建立了通用的数字液压缸传递函数模型。利用所建模型，分析了参数意义和系统特性，并结合具体参数进行了仿真验证。结果表明，受负载和非对称结构影响，数字液压缸正反向运动特性存在差异;系统性能由内反馈回路的结构参数决定，系统稳定性良好。

Modeling and Analysis of Digital Hydraulic Cylinder Based on Transfer Function

Considering power match and characteristics of asymmetrical structure, setting the position with the minimum hydraulic spring stiffness as the orginal point, a transfer function of valve-controlled asymmetrical cylinder was deduced, a reasonable expression to count hydraulic natural frequency was given, and then a universal transfer function model of the digital hydraulic cylinder was established. Based on the model, meaning of parameters and system characteristics were analysed. And using real parameters, confirmatory simulation experiments were carried out. The results reveal that, load and the asymmetrical structure of digital hydraulic cylinder account for the performance differences between the two motion directions-positive and negative. System performance is decided by the structural characteristics of inner feedback loop, and the good stability is showed.