【作者】 董彩云；

【导师】 姜万录； 张齐生；

【作者基本信息】 燕山大学 ， 机械电子工程， 2007， 硕士

【摘要】 针对电液伺服系统的控制特点和性能要求,将滑模变结构控制策略应用到典型电液伺服控制系统中,进行了详细的理论分析和实验研究。实际电液伺服系统存在诸多非线性影响因素,并且存在着比较大的不确定性,此外还不可避免地存在外部负载干扰。而实际系统要求稳态误差小、快速性好、鲁棒性强,这就给控制系统的设计带来了很大的困难。为了克服这些不利因素,满足系统要求,本文将滑模变结构控制策略应用于电液伺服控制系统中。滑模变结构控制的主要特点是:当系统状态穿越状态空间的不同区域时,反馈控制器的结构按照一定的规律发生变化,使得控制器对伺服系统的内在参数变化和外在负载扰动等因素具有较强鲁棒性,从而保证系统能够达到期望的性能指标要求。本文首先对典型电液伺服控制系统进行了理论分析,建立了数学模型,计算出了系统的有关参数,并通过仿真验证了滑模变结构控制算法的合理性和有效性。其次,进行了实验研究,采用LabVIEW软件编制出实时控制程序,以材料试验机为被控对象进行实时控制,取得了良好的控制效果;结果表明:与PID控制相比,滑模变结构控制具有更好的动态特性。实验还分析了供油压力对动态响应特性的影响,以及控制器参数变化对系统性能的影响。从而在理论分析以及实验中均证明了应用滑模变结构控制策略时,系统具有快速性好,控制平滑,易于微机实现,动态特性良好,鲁棒性强等优点,为工程应用奠定了基础。更多还原

【Abstract】 In accordance with control characteristics and performance demand of the electro-hydraulic servo system, a new control strategy of sliding mode variable structure control is applied in the general electro-hydraulic servo system, then a lot of simulation and experiment is done.There are some nonlinear factors, great indeterminacy and load disturbance in the real electro-hydraulic servo system inevitably. At the same time, we expect the steady-state error of the system is small, and the adjusting time is short. Therefore, it is very difficult for the designer to design the system. To overcome these disadvantages, and meet the demand of the system, the variable structure control with sliding mode approach is presented in this paper. The main characteristic of the sliding mode variable structure control is that: when the state of the system goes through the different areas of the state space, the structure of the feedback controller changes as some law. Thus, the system is robust to the inner parameter variation and outer environment interference and the system has better dynamic performanceIn the paper, having analyzed and studied the electro-hydraulic servo system in theory, its mathematical model is set up, and the involved parameters are calculated and determined. Further, a great number of simulation experiments verified the algorithm is effective. At last, by means of experiments, a real-time control program by LabVIEW is realized to control material testing machine. The results are proved to be satisfactory. And the influence of the supplying pressure and the control parameters with the system’s dynamic characteristics is studied. Therefore, not only on the theory and simulation but also in the real system experiments, by using the sliding mode control, the system have the characteristics such as the fast speed quality, smooth control, better dynamic performance following with that being carried out easily for microcomputer; which lay a foundation to apply them in practices and production.更多还原