基于内模的电液位置力复合阻抗控制策略

Internal Model-Based Electro-Hydraulic Position-Force Composite Impedance Control Strategy

在液压机、矫直机等液压成型机械设备中,常常需要对工作机构的位置和压力同时控制。由于电液伺服系统位置控制和力控制在机理上不同,位置控制和力控制切换时会产生冲击,阻抗控制是实现其平滑切换的一种有效方法。考虑电液力伺服系统强非线性、参数时变等特性,提出了一种基于力内模的阻抗控制策略,在推导阀控缸力数学模型的基础上,设计了力内模控制器。该控制策略实现了位置和力的平滑切换,且力控制的动态响应性能好,鲁棒性强。

In hydraulic press,straightening machine and other hydraulic forming machinery and equipment,it is often necessary to control the position and pressure of the working mechanism at the same time.Because the position control and force control of electro-hydraulic servo system are different in mechanism,the switching between position control and force control will produce impact.Impedance control is an effective method to achieve smooth switching.Considering the characteristics of strong nonlinearity and time-varying parameters of electro-hydraulic force servo system,an impedance control strategy based on force internal model is proposed in this paper.Based on the mathematical model of valve-controlled cylinder force,the force internal model controller is designed.The control strategy realizes the smooth switching of position and force,and the force control has good dynamic response performance and strong robustness.