三轴液压仿真转台非线性多输入多输出QFT控制器设计

Nonlinear MEMO QFT controller design for three-axis hydraulic simulator

三轴液压仿真转台本质上是非线性变参数多输入多输出系统。系统负载、油源压力、增益的变化及耦合作用随速度,加速度的变化造成很大的参数不确定性。针对液压转台提出一种基于SIMULINK模型线性化的多输入多输出非线性定量反馈设计方法。其本质是找到液压伺服系统一系列控制特性最差的运行点,直接用它们的频率响应集合来综合非线性定量反馈控制器。这种方法简化了目前的QFT多输入多输出控制系统设计方法,显示了很大的优越性。文中举例说明这种方法的效果。

Three-axis hydraulic simulator is essentially a nonlinear multi-input multi-output (MIMO) system with varying parameters. The variations of system load, pump pressure and moment coupling among frames give a large parameter uncertainty. The author proposed a nonlinear MIMO quantitative feedback design method based on Simulink linearization for hydraulic simulator. Its essence is to find out a series of the worst operating points for hydraulic systems under different working conditions, and use their frequency-response sets to synthesis a nonlinear QFT(Quantitative Feedback Theory)controller. This method shows great superiority when comparing with traditional MIMO QFT method. An example was given to illustrate its efficacy.