电液比例系统的H_∞鲁棒性控制设计

Design of an H_∞ Robust Controller for an Electro-hydraulic Proportional System

针对电液比例系统中系统控制数学模型参数时变要求控制器鲁棒性强的特点,通过分析电液比例系统的物理模型,利用线性分式变换(LFT)方法,引入乘性不确定性参数,给出了参数时变的电液比例模型,并得出了具有参数不确定性系统状态空间函数模型。运用线性矩阵不等式(LM I)的H∞控制器的处理方法,设计出基于H∞控制的电液比例系统控制器。利用该控制器可有效的抑制参数时变对系统输出的影响。仿真表明该控制器在较大不确定参数的变动下,控制器仍然能够使系统具有较好的输出性能,结果说明该鲁棒控制器的有效性。

Due to the parameter＇s uncertainty in the electro-hydraulic proportional system, a system model with uncertain parameters is built by analyzing the electro-hydraulic model, using the method of linear fractional transformation （LFT） and adopting the multiplying uncertain parameters. The uncertain parameter state space equation of the electro-hydraulic proportional system is proposed to design the robust controller based on the H∞ control by the method of H∞ theory using linear matrix inequalities （LMI）. Simulation results show that the robust controller still have good output performance under the condition of large variable range of the uncertain parameters. The results demonstrate the effectiveness of this method.