一类非线性不确定非匹配时滞系统的鲁棒滑模控制

针对一类带有不匹配非线性不确定的线性时滞系统,基于稳定性理论,提出一种新的依赖于时滞的滑动模控制策略。该控制策略保证闭环系统滑动阶段的存在性,并在此基础上证明滑动模态运动的稳定性。最后通过仿真例子看出,抖振现象被大大减弱,这进一步说明该控制策略的可行性和有效性。     

一类非线性不确定中立型延迟系统的鲁棒滑模控制

讨论一类非线性不确定中立型系统的鲁棒滑模控制问题。通过选择依赖于当前状态和延迟状态的滑动面。就线性矩阵不等式（LMIs）的形式给出使得闭环系统渐近稳定的充分条件。当LMIs有可行解时。可以通过我们构造的控制使得可达条件得到满足。具体算例的仿真结果说明此法的有效性。     

Fuzzy Sliding Mode Control for Discrete Nonlinear Systems

Sliding mode control is introduced into classical model free fuzzy logic control for discrete time nonlinear systems with uncertainty to the design of a novel fuzzy sliding mode control to meet the requirement of necessary and sufficient reaching conditions of sliding mode control. The simulation results show that the proposed controller outperforms the original fuzzy sliding mode controller and the classical fuzzy logic controller in stability, convergence and robustness.     

广义不确定系统的模糊滑模控制*

研究了广义不确定系统的模糊滑模控制问题。控制结构中采用模糊系统来补偿动态不确定性,利用李亚普诺夫理论,证明了闭环系统的所有状态是全局有界的。     

一类非线性系统的自适应模糊滑模控制

对一类具有不确定性的非线性系统,根据滑模控制原理并利用模糊系统的逼近能力,提出了一种自适应模糊滑模控制系统的设计方法.控制结构中采用模糊系统自适应朴偿过程的不确定性.利用李雅普诺夫理论,证明了控制算法是全局稳定的,跟踪误差可收敛到零的一个邻域内.     

广义系统的有限时间滑模变结构控制

研究了一类广义系统的有限时间滑模变结构控制问题。通过非奇异线性变换把广义系统变换成受限等价形式,利用Lyapunov函数的方法,提出了一种新型的有限时间滑模变结构控制策略,给出了特殊的开关型滑模面,设计了相应的滑模变结构控制器,使得闭环系统渐进稳定,实现了滑模运动,保证了在滑模面上系统状态变量在有限时间内到达平衡点。给出了可行性算例,说明了设计的有效性。     

Robust Sliding Mode Observer based Fault Estimation for Certain Class of Uncertain Nonlinear Systems

This paper proposes a new scheme for estimating the actuator and sensor fault for Lipschitz nonlinear systems with unstructured uncertainties using the sliding mode observer (SMO) technique. Initially, a coordinate transformation is introduced to transform the original state vector into two parts such that the actuator faults only appear in the dynamics of the second state vector. The concept of equivalent output error injection is then employed to estimate the actuator fault. The effects of system uncertainties on the estimation errors of states and faults are minimized by integrating an uncertainty attenuation level into the observer. The sufficient conditions for the state estimation error to be bounded and satisfy a prescribed performance are derived and expressed as a linear matrix inequality (LMI) optimization problem. Furthermore, the proposed actuator fault estimation method is extended to sensor fault estimation. Finally, the effectiveness of the proposed scheme in estimating actuator and sensor faults has been illustrated considering an example of a single‐link flexible joint robot system.     

H∞ Control for Continuous‐Time Mean‐Field Stochastic Systems

An H_∞‐type control is considered for mean‐field stochastic differential equations (SDEs) in this paper. A stochastic bounded real lemma (SBRL) is proved for mean‐field stochastic continuous‐time systems with state‐ and disturbance‐dependent noise. Based on SBRL, a sufficient condition is given for the existence of a stabilizing H_∞ controller in terms of coupled nonlinear matrix inequalities.     

H∞ Control and Sliding Mode Control of Magnetic Levitation System

In this paper, H∞ disturbance attenuation control and sliding mode disturbance estimation and compensation control of a magnetic levitation system are studied. A magnetic levitation apparatus is established, and its model is measured. Then the system model is feedback linearized. A H∞ controller is then designed. For comparison, a sliding mode controller and a PID controller also were designed. Some experiments were performed to compare the performance of the H∞ controller, the sliding mode controller and the PID controller.     

一类非线性系统的多面滑模控制

提出一种基于模糊ＣＭＡＣ神经网络的多面滑模变结构控制算法,其特点是无须已知不确定性函数及其各阶导数的上界,与经典设计广阔霜比,所提出的方案允许非参数化不确定性,仿真实例显示了该方法的有效性。     

Robust H∞ Control Problem For General Nonlinear Systems With Uncertainty

In this paper, both state and output feedback robust H^∞ control problems for general nonlinear systems with norm‐bound uncertainty are considered. Sufficient conditions for the existence of robust output feedback H^∞ controller are provided. State space formulas for robust H^∞ output controller are provided.     

Singular H∞ Suboptimal Control for a Class of Nonlinear Cascade Systems

In the present paper singular state feedback _∞ suboptimal control for a class of nonlinear cascade systems is addressed. Under the assumption that a regular state feedback _∞ suboptimal control problem is solvable for a particular subsystem of the cascade system, an auxiliary nonlinear system is defined. It is shown that a state feedback solution to the singular _∞ suboptimal control problem for the auxiliary system also applies to the original problem. The advantage of the auxiliary problem to the original problem is that the auxiliary penalty variable has lower dimension than the original penalty variable. It is shown how this fact can simplify the problem considerably for the case when the auxiliary system can be strongly input-output decoupled. The theory is applied to a problem of a rigid spacecraft with actuator dynamics. Application to the special case when a subsystem of the nonlinear cascade system is passive is also considered.     

H∞ Control with Transients for Singular Systems

In this paper, the problem of a generalized type of H_∞ control is investigated for continuous‐time singular systems, which treats a mixed attenuation of exogenous inputs and initial conditions. First, a performance measure that is essentially the worst‐case norm of the regulated outputs over all exogenous inputs and initial conditions is introduced. A necessary and sufficient condition is obtained to ensure the singular system to be admissible and the performance measure to be less than a prescribed scalar. Based on the criterion a sufficient condition for the existence of a state‐feedback controller is established in terms of linear matrix inequalities. Moreover, the relationship between the performance measure and the standard H_∞ norm of the system is provided. Two numerical examples are given to demonstrate the properties of the obtained results.     

Finite-time Sliding Mode Control Design for a Class of Uncertain Conic Nonlinear Systems

This paper studies the sliding mode controller design problems for a class of nonlinear system. The nonlinear function is considered to satisfy conic-type constraint condition. A novel finite-time boundedness (FTB) based sliding mode controller design theory is proposed. And then a sufficient condition is obtained in terms of linear matrix inequalities (LMIs), which guarantees the resulted sliding mode dynamics to be FTB wrt some predefined scalars. Thereafter, a FTB-based sliding mode control (SMC) law is synthesized to ensure the state of the controlled system is driven into a novel desired switching surface s(t)=c (c is a constant) in a finite time. Simulation results illustrate the validity of the proposed FTB-based SMC design theory.      

广义系统滑动模控制的研究

研究广义线性系统的滑动模控制问题。给出了新的变结构控制设计方法,分析了现有文献的不足,并对已有控制设计进行了对比。     

约束非线性系统的滑模预测控制方法

将预测控制和滑模控制结构起来,提出一种新的非线性模型预测控制方法,通过对系统状态预测得到切换函数预测值,求解约束开环优化求得预测控制律,并将当前时刻的控制作用于对象,下一时刻重复此过程,该方法具有预测控制在线处理约束及滑模控制滑动模态对干扰的不变性的优点,分析了零终端滑模约束模型预测控制的稳定性。     

一类非线性系统的自适应滑模模糊控制

针对一类具有多个子系统的欠驱动非线性系统提出了一种自适应滑模模糊控制方法.首先通过分析模糊控制与边界层滑模控制的相似性,提出了滑模模糊控制方法;然后根据滑模面斜率和各子系统控制对于系统动态性能的影响,分别采用模糊推理根据系统状态自动地实时调节滑模面斜率和各子系统在系统控制中的作用;最后通过简单的滑模模糊控制器实现对具有多个子系统的欠驱动非线性系统的控制.将该方法应用于吊车的运输控制中,仿真结果证明了其有效性和鲁棒性.     

广义系统的终端滑模变结构控制

研究广义系统的终端滑模控制问题,通过线性奇异变换将广义系统化为受限等价形式,在此基础上给出相应的终端滑模超曲面和终端滑模控制律．研究结果表明,系统状态变量能以较快的收敛速度在有限时间内进入滑模超曲面并最终到达平衡点。     

一类非线性不确定系统的高阶积分自适应滑模控制

为有效改善传统积分滑模在一类非线性不确定系统的应用中存在的抖振问题,结合有限时间收敛理论、高阶积分滑模理论和自适应控制理论,提出了一种高阶积分自适应滑模控制方法;该方法通过选取有限时间收敛反馈量和设计高阶积分滑模面,不仅确保了系统状态误差在有限时间内的收敛性,而且还保证了系统具备对不确定性干扰的抑制能力;同时,当系统的不确定项的边界范围无法预先确定时,采用自适应方法对滑模控制的趋近速率进行估计;仿真结果表明所提方法能够有效抑制非线性不确定系统的抖动,并具有较高的控制精度.     

Output Feedback Terminal Sliding Mode Control for a Class of Second Order Nonlinear Systems

In this study, a novel output feedback terminal sliding mode control (TSMC) approach is proposed for a class of second order nonlinear systems in light of the equivalent output injection sliding mode observer (SMO) method and TSMC principle. The SMO method is applied to reconstruct full states in finite time and the non‐singular TSMC algorithm is designed to stabilize system states to equilibrium points in finite time. The corresponding stability analysis is presented. An indispensable illustrative example is bench tested to validate the effectiveness of the proposed approach.