【作者】 胡永生；

【导师】 杨洁明；

【作者基本信息】 太原理工大学 ， 机械电子工程， 2008， 硕士

【摘要】 本文首先介绍了电液伺服控制系统的组成及发展历程,并且分析了电液伺服控制系统的非线性和不确定性的特点及产生的原因,而后介绍了滑动模态变结构控制的发展与研究现状。作为一种鲁棒性强的控制方法,变结构控制可通过控制器结构的不断调整和变化,有效地控制具有参数变化和外部扰动的被控制对象,这与具有不确定性(包括参数变化,外部扰动与非线性)的电液伺服系统的控制要求是一致的,因此变结构控制在电液伺服控制系统设计当中受到广泛重视。为了应用到电液伺服控制系统中,本文详细阐述了变结构控制理论的基本概念、基本问题,建立了电液伺服系统的各个组件的数学模型,进而建立了电液伺服系统的理论模型。然后从实验室测得电液伺服系统的液压缸和伺服阀及其它环节的的参数,计算后分别确定了各个组件的传递函数,最终确定了系统的传递函数方块图。本课题的另一项工作是在建立电液伺服系统的模型后,使用滑模变结构控制的比例切换控制法设计滑模控制器,采用S函数描述滑模控制器和电液伺服系统的模型,继而在Matlab/Simulink里建立整个系统的仿真模型。当系统存在不定性时,作者分别采用阶跃信号和正弦信号作为参照信号,将滑模变结构控制和PID控制进行仿真比较。结果表明:滑模变结构控制算法优于PID算法。为了建立更加精确的液压系统的模型,提高整个控制系统的性能,本文还建立了基于ARMSim/Simulink的联合仿真平台,在该平台上进行了滑模变结构控制和PID控制的仿真比较研究。此外,还将联合仿真平台里的模型与在Matlab/Simulink里建立的模型的控制性能作了比较,结果表明:在Simulink仿真平台中,滑模变结构控制系统具有更快的响应时间、更好的动静态性能和更强的鲁棒性;在ARMSim/Simulink的联合仿真平台中,变结构控制系统的响应时间也小于PID控制系统;整体上来看ARMSim/Simulink的联合仿真平台的控制性能好于Simulink仿真平台。更多还原

【Abstract】 Firstly this paper introduces the composition and the development of the electro-hydraulic servo control system, and analyses nonlinear characteristic and uncertainties of the electro-hydraulic servo control system along with their causes, then the development and research status quo of the sliding mode variable structure control is introduced. As a robust-control method, variable structure control can effectively control the systems which exist parameters uncertainties and disturbance by adjusting and changing the controller, which is consistent with the control requirements of electro-hydraulic servo control system including uncertainties (parameters uncertainties, external disturbances and nonlinearities), therefore sliding mode variable structure control theory is highly regarded in the design of electro-hydraulic servo control system. In order to apply to electro-hydraulic servo control system, the paper elaborates on basic concepts and basic issues of the variable structure control, and establishes the mathematical models of all parts in electro-hydraulic servo system, so theoretical model of electro-hydraulic servo system is formed. From the laboratory, parameters involved in the hydraulic cylinders and the servo valve and other parts of electro-hydraulic servo system are measured and calculated, then the every transfer function of the components is determined, and ultimately the system’s transfer function block diagram is determined.After the establishment of the electro-hydraulic servo system model, sliding controller is also designed using the proportion switch control of the sliding mode variable structure control theory, and using S-function describes models of the sliding mode controller and electro-hydraulic servo system, then simulation model of the whole system is established in Matlab/Simulink. When the system exists uncertainties, the author compares sliding mode control with PID control adopting step signal and sine signal as a reference. The simulation results show that: sliding mode control algorithm is better than PID algorithm. In order to establish a more precise model of the hydraulic system and improve the performance of the whole control system, the paper has also established co-simulation platform based on ARMSim/Simulink, and made comparative study of the simulation between a sliding mode control and PID control. In addition, control performance of the model established in co-simulation platform is compared with that in Matlab/Simulink simulation platform, the results show that: sliding mode control system has faster response time, better static and dynamic performance and more robust than PID control system in Simulink simulation platform; in ARMSim/Simulink co-simulation platform, response time of variable structure control system is also less than the PID control system; on the whole, control performance in ARMSim/Simulink co-simulation platform is better than Simulink simulation platform.更多还原