基于鲁棒控制的液压伺服系统的半实物仿真研究

【作者】 李梦辉；

【导师】 李虹；

【作者基本信息】 太原科技大学 ， 控制理论与控制工程， 2011， 硕士

【摘要】 电液位置伺服控制系统是当今控制领域重要的组成部分。本文的研究对象为轧机液压压下厚度控制系统试验装置,是一个典型的电液位置伺服控制系统。针对电液位置伺服系统中存在的参数不确定性的特点,本文设计了两种鲁棒控制器,并通过DSP控制器实现了所设计的鲁棒控制器。首先,文章建立了电液位置伺服系统的数学模型,并根据系统数学模型开环传递函数的灵敏度函数的奈奎斯特曲线上的点,与临界稳定点(-1,j0)点的距离,设计了系统的鲁棒PID控制器。在系统数学模型参数发生摄动的情况下,分析了控制系统的单位阶跃响应曲线与基于幅值与相角裕度所设计的PID控制器控制下的系统单位阶跃响应曲线之间的差别,验证了所设计的鲁棒PID控制器的鲁棒性能。其次,本文研究了控制系统中存在的不确定性的因素及其对系统的影响。并由此介绍了鲁棒控制器设计研究的由来,以及H_∞控制器设计的理论基础和设计H_∞混合灵敏度控制器时加权函数选取的原则。根据H_∞混合灵敏度控制器的设计方法,设计了轧机液压压下厚度系统试验装置的H_∞混合灵敏度控制器。最后,根据文章设计的鲁棒PID控制器和H_∞混合灵敏度控制器,使用数字信号处理器TMS320F2812实现了两种鲁棒控制器的功能。为了验证所设计的DSP鲁棒控制器的控制性能,设计了电液位置伺服系统数学模型的电模拟器。通过DSP鲁棒控制器与电模拟器联合试验,以及控制系统单位阶跃响应曲线与仿真曲线的对比,证明了所设计的DSP鲁棒控制器与所预想的控制效果基本一致。更多还原

【Abstract】 Electro-hydraulic position servo control system is the important part of the control fields nowadays. Thickness system of hydraulic mill stand roll-gap is the test device, which is used in the study, and the system is a typical electro-hydraulic position servo control system. For the feature of the parameter uncertainty in the electro-hydraulic position servo system, in the paper, two robust controllers are designed, and which are achieved by the DSP controller.Firstly, the paper establishes mathematical model of the electro-hydraulic position servo control system, and designs a robust PID controller of the system, based on the distance between the points of the Nyquist curve of the sensitivity function of the open loop transfer function of the system mathematical model and the critical stable point (-1,j0).In the case of increasing and decreasing the parameters of the mathematical model of the system, the paper analysis the differences between the unit step response curve of the control system and the unit step response curve of the PID controller based on the amplitude and phase margin, demonstrates robust performance of the robust PID controller.Secondly, the paper describes the uncertainty factors which the system exists and the impact of the system. And thus, the paper describes the origin of the design of robust controller, and the theory basis of designing H_∞controller and the selection principle of the weighting function when someone design the mixed sensitivity H_∞controller. Based on the method of designing the mixed sensitivity H_∞controller, the paper designs the mixed sensitivity H_∞controller of thickness system of hydraulic mill stand roll-gap.Finally, according to the robust PID controller and the mixed sensitivity H∞controller which the article designs , the paper achieves the function of two robust controller used the digital signal processor of TMS320F2812. To verify the controlled performance of the DSP robust controller, the paper designs the electrical simulator of mathematical model of the electro-hydraulic position servo control system. Through the test of the DSP robust controller and the electrical simulator, and the comparison of the unit step response curve of the system with the simulation curve , the paper proves that the DSP robust controller which is designed is consistent with the desired control.更多还原