【作者】 华长春；

【导师】 关新平；

【作者基本信息】 燕山大学 ， 控制理论与控制工程， 2002， 硕士

【摘要】 众所周知非线性系统广泛存在于客观世界，时滞为一般系统所固有的，而不确定性在所难免，因此研究不确定非线性时滞系统的鲁棒稳定性分析及控制显得特别重要，是当前控制界研究的热点和难点。本文在现有文献的基础之上，对非线性时滞系统的鲁棒稳定性及控制方面做了一些工作。 本文首先研究了一类不确定Lurie时滞系统的鲁棒绝对稳定性问题，不确定项范数有界。通过构造特殊的李亚普诺夫函数，分别考虑了时滞相关和时滞无关两类情形，得到了系统鲁棒绝对稳定的充分条件。 然后，结合滑模变结构控制思想和自适应模糊控制思想，论文进一步研究了不确定非线性时滞系统的滑模变结构自适应模糊控制，首先设计了时滞相关的滑模面，能保证滑模运动指数稳定，然后设计了鲁棒自适应反馈控制器，使系统的状态有限时间内到达滑模面，最终使相应的闭环系统渐近稳定。 在非线性时滞关联大系统方面，论文分别对两类系统作了研究。首先考虑了内部具有非线性扰动的关联时滞系统，研究了其输出反馈控制问题，设计了反馈控制器使系统渐近稳定。其次，研究了时变非线性关联时滞系统的控制问题，时变时滞存在于关联项中，且关联项中可以存在强非线性环节，对此系统文中设计了鲁棒分散自适应反馈控制器，能使相应的闭环系统一致有界稳定。 最后，对一类非线性时滞混沌系统作了研究，假设时滞项不是满足一般的一阶线性有界条件，而是高阶有界条件，且界未知，研究了其控制问题。文中基于自适应控制策略和非线性反馈策略分别提出了两类不同的反馈控制器，使相应的闭环系统一致有界稳定。这两类控制器均是时滞无关的，与以往的时滞相关的结果相比，我们的结果更容易实现，且我们考虑了系统可能存在不确定的情形，所以也更具有一般性。更多还原

【Abstract】 As we know that nonlinear systems exist in the world extensively, time delays are inherent in systems and uncertainties are not avoidable, so it is important to investigate the stability analysis and control of uncertain nonlinear systems with time delays. Now it is the hotspot and also the difficulty in control domain. Based on the existing literature, some work has been done in this paper on stability analysis and control of nonlinear time delay systems.In this paper, firstly absolute stability problem of uncertain Lurie time delay systems has been considered. By constructing special Lyapunov functions, We obtain sufficient conditions for the stability of systems dependent of the time delays and independent of the time delays respectively.Second, based on the sliding mode variable structure idea and adaptive fuzzy idea, this paper further considers variable structure adaptive fuzzy control for nonlinear time delay systems. The sliding mode is constructed dependent of the time delays, which can render the sliding motion exponentially stable. Then the robust adaptive feedback controllers are constructed, which can render the systems states reach the sliding mode in limited time. Therefore, the controllers will render the closed-loop systems asymptotically stable.This paper investigates two classes of nonlinear interconnected systems with time delays. Firstly, robust control problem for a class of interconnected system with nonlinear disturbances is considered, and output feedback controller is constructed to render the closed-loop systems asymptotically stable. Also a class of time varying nonlinear systems with time delays are considered with time varying delays and strong nonlinear sections in interconnections, for such systems a class of decentralized feedback controllers are constructed, which can render the closed-loop systems uniformly ultimately bounded stable.In the end, a class of nonlinear time delay chaotic systems are investigated, in which the time delay sections are not bounded by first-order polynomial, butbounded by high-order polynomial with unknown gains. For such systems, two classes of feedback controllers are proposed, which are both independent of time delays and can render the closed-loop systems stable in the sense of uniform ultimate boundedness. Compared with the existing resuts, the results of this paper are more applicable, and we consider the uncertain case, so the results are more general.更多还原