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1.
针对一类具有输出反馈耦合的离散非线性系统,将过程的非线性状态空间模型等效为线性时变状态空间模型;然后利用最小二乘法辨识系统参数,并通过在目标函数中引入系统状态的变化给出一种具有类似离散PI最优调节器结构的新型自适应预测函数控制器.由于引入了新的优化目标函数,该控制器控制效果与鲁棒性要优于仅考虑预测输出误差的传统预测函数控制器.仿真结果表明,该控制器优于经典离散PI最优调节器.  相似文献   

2.
张日东  王树青 《控制与决策》2007,22(10):1103-1107
针对一类具有输出反馈耦合的离散非线性系统,将过程的非线性部分通过支持向量机转化为全局线性状态空间模型,并在目标函数中引入系统状态的变化,给出一种类似于离散PI最优调节器的新型预测控制器.该方法不需要在线辨识系统参数,因为系统的内模已转换成全局离线模型.由于引入了新的优化目标函数,该控制器的控制效果和鲁棒性优于仅考虑预测输出误差的传统预测控制器.仿真结果表明,它也优于经典离散PI最优调节器.  相似文献   

3.
一类离散时间切换系统鲁棒控制器设计   总被引:7,自引:0,他引:7  
考虑一类非线性离散时间切换系统的鲁棒二次镇定和渐近镇定问题.利用公共李亚普诺夫函数方法和多李亚普诺夫函数方法,分别设计了切换系统鲁棒状态反馈控制器和输出反馈控制器,保证了切换系统的二次稳定性和渐近稳定性.仿真结果验证了所提出算法的有效性.  相似文献   

4.
基于精确线性化的MIMO双线性系统预测函数控制   总被引:4,自引:1,他引:4  
针对典型多输入多输出双线性系统, 提出了基于非线性过程精确反馈解耦线性化的预测函数控制方法这是一种分层的控制策略, 首先设计一个静态的非线性状态反馈, 使得闭环系统是输入输出解耦和线性的;然后设计一组单输入单输出预测函数控制器, 下层为上层预测函数控制提供一组单输入单输出模型, 而上层预测函数控制以其固有的鲁棒性来补偿参数变化和解耦线性化的近似性, 并以纸机加压网前箱为例进行了仿真实验, 结果是令人满意的.  相似文献   

5.
针对一类满足扇形界条件的不确定模糊模型描述的非线性系统,提出一种输出反馈鲁棒预测控制方法.该方法将鲁棒预测控制的Min-Max优化问题转化为具有LMI约束的线性目标最小化问题,并且不需系统状态完全可测,仅仅利用系统测量输出和不可测状态的界限值来确定保证闭环系统鲁棒稳定的输出反馈控制器.仿真实验证明了该方法的有效性.  相似文献   

6.
约束时变不确定离散系统的输出反馈预测控制综合   总被引:2,自引:1,他引:2  
研究多包描述系统的离线型输出反馈预测控制.已有一方法首先综合状态反馈预测控制,满足输入/ 状态约束;而在设计观测器时,不再考虑输入/ 状态约束.本文则首先给出观测器,并给出一组不等式条件使得真实状态、观测状态和观测误差都保持在同一个椭圆内部,以便采用线性矩阵不等式处理输入/ 状态约束.基此,本文离线计算一椭圆序列,每个椭圆对应一控制律和一观测器,而在线的实时控制律和观测器则从该序列中选择,使得闭环系统具有稳定性保证.仿真例子说明了本文方法的有效性.  相似文献   

7.
针对干扰作用下的非线性网络控制系统,给出了带一个自由控制作用的输出反馈预测控制方法.首先,利用区间二型T-S模糊模型描述具有参数不确定性的非线性对象,采用马尔科夫链描述系统中的随机丢包过程,由此建立了丢包网络环境下的非线性网络控制系统的数学模型.然后,通过引入二次有界技术得到了干扰作用下网络控制系统的稳定性描述方法,并在此基础上给出了状态观测器的线性矩阵不等式条件.最后,基于估计状态,通过将无穷时域控制作用参数化为一个自由控制作用加一个线性反馈律得到了输出反馈预测控制方法.论文的特色在于构建了在线更新误差椭圆集合的基本方法,满足了约束条件下输出反馈预测控制保证稳定性的要求.仿真例子验证了所提方法的有效性.  相似文献   

8.
基于并行支持向量机的多变量非线性模型预测控制   总被引:2,自引:0,他引:2  
提出一种基于并行支持向量机的多变量系统非线性模型预测控制算法.首先,通过考虑输入、输出间的耦合,建立基于并行支持向量机的多步预测模型;然后,将该模型用于非线性预测控制,提出新的适用于并行预测模型的反馈校正策略,得到最优控制律.连续搅拌槽式反应器(CSTR)的控制仿真结果表明,该算法的性能优于基于并行神经网络的非线性模型预测控制和基于集成模型的非线性模型预测控制.  相似文献   

9.
基于EGA的非线性预测控制器   总被引:3,自引:0,他引:3       下载免费PDF全文
王慧燕  诸静 《控制与决策》2002,17(2):252-254
提出一种基于Volterra模型的非线性预测控制器,采用收敛精度高,高速快的EGA算法动求解控制律,反馈校正中考虑了误差和输出变化趋势影响的双重抑制,对一类非线性系统的仿真研究表明该预测控制器影响应快,具有较强的鲁棒性,对于改善非线性预测控制策略的性能非常有益。  相似文献   

10.
本文针对一类在任意切换信号作用下的切换非线性系统, 研究了其输出反馈周期事件触发控制问题. 所考 虑的非线性系统采用非严格反馈形式且含有未知时变控制系数. 在本文中, 仅利用采样时刻的系统输出. 为了估计 系统的不可量测的状态, 基于采样的系统输出构造了降维状态观测器. 为了减少通信资源的利用, 提出了一种新的 输出反馈周期事件触发策略, 该策略包含仅利用事件触发时刻的信息构造的输出反馈事件触发控制器以及仅在采 样时刻间歇性监测的离散事件触发机制. 通过选取可容许的采样周期及合适的公共Lyapunov函数, 证明了闭环系统 在任意切换下全局渐近稳定. 最后, 通过将本文中所给出的控制方案应用到数值算例中验证了其有效性.  相似文献   

11.
单相有源电力滤波器非线性统一控制策略   总被引:2,自引:0,他引:2  
目前有源电力滤波器控制策略都采用电流内环和电压外环的双环控制.本文提出了一种基于精确反馈线性化的单相有源电力滤波器统一控制策略.在单相有源电力滤波器仿射非线性模型基础上,通过求解偏微分方程得到一个包含补偿电流变量和直流侧电压变量的输出函数,并推导出了其状态反馈精确线性化非线性控制律,将原非线性系统转换成微分同胚的二阶线...  相似文献   

12.
A robust fuzzy output sliding control for nonlinear robotic arms is proposed in this paper. The proposed method not only retains the advantages of the conventional sliding mode control such as robustness against parameter variations and external disturbances, but also uses measurable output signals to define the sliding surface function. A fuzzy controller is developed to modify the control law to avoid state measurement. Control system stability is proved by using the Lyapunov stability theorem. The system robustness is guaranteed. Simulations results demonstrate the validity and effectiveness of the proposed method for uncertain nonlinear robotic arms.  相似文献   

13.
In this paper, an adaptive output‐feedback control problem is investigated for nonlinear strict‐feedback stochastic systems with input saturation and output constraint. A barrier Lyapunov function is used to solve the problem of output constraint. Then, fuzzy logic systems are used to approximate the unknown nonlinear functions, and a fuzzy state observer is designed to estimate the unmeasured states. To overcome the difficulties in designing the control signal in the saturation, we introduce an auxiliary signal in the n + 1th step in the deduction. By combining Nussbaum technique and the adaptive backstepping technique, an adaptive output‐feedback control method is developed. The proposed control method not only overcomes the problem of the compensation for the nonlinear term from the input saturation but also overcomes the problem of unavailable state measurements. It is proved that all the signals of the closed‐loop system are semiglobally uniformly ultimately bounded. Finally, the effectiveness of the proposed method is verified by the simulation results.  相似文献   

14.
This paper investigates the problem of global output feedback stabilisation for a class of uncertain nonlinear systems, where output function is time-varying and continuous, and multiple time delays exist in system state at the same time. A double-domination method is used to capture time-varying measurement error and delayed states. The control strategy is presented based on the choice of Lyapunov–Krasovskii functionals and the construction of a novel state observer without using the information on the output function and nonlinearities. A simulation example is given to show the efficiency of the proposed control scheme.  相似文献   

15.
The paper presents a new nonlinear predictive control design for a kind of nonlinear mechatronic drive systems, which leads to the improvement of regulatory capacity for both reference input tracking and load disturbance rejection. The nonlinear system is first treated into an equal linear time-variant system plus a nonlinear part using a neural network, then an iterative learning linear predictive controller is developed with a similar structure of PI optimal regulator and with setpoint feed forward control. Because the overall control law is a linear one, this design gives a direct and also effective multi-step prediction method and avoids the complicated nonlinear optimization. The control law is also an accurate one compared with traditional linearized method. Besides, changes of the system state variables are considered in the objective function with control performance superior to conventional state space predictive control designs which only consider the predicted output errors. The proposed method is compared with conventional state space predictive control method and classical PI optimal control method. Tracking performance, robustness and disturbance rejection are enlightened.  相似文献   

16.
To improve transient performance of output response, this paper applies composite nonlinear feedback (CNF) control technique to investigate semi-global output regulation problems for linear systems with input saturation. Based on a linear state feedback control law for a semi-global output regulation problem, a state feedback CNF control law is constructed by adding a nonlinear feedback part. The extra nonlinear feedback part can be applied to improve the transient performance of the closed-loop system. Moreover, an observer is designed to construct an output feedback CNF control law that also solves the semi-global output regulation problem. The sufficient solvability condition of the semi-global output regulation problem by CNF control is the same as that by linear control, but the CNF control technique can improve the transient performance. The effectiveness of the proposed method is illustrated by a disturbance rejection problem of a translational oscillator with rotational actuator system.  相似文献   

17.
陈海永  孙鹤旭  王宏 《控制与决策》2011,26(8):1169-1174
针对一类仿射非线性有界动态随机系统,提出一种最优概率密度函数(PDF)跟踪控制算法,使得系统的输出PDF跟踪给定的PDF.首先利用线性B样条解耦得到仿射非线性状态方程和PDF逼近方程,使PDF跟踪转化为状态方程输出权值的跟踪;然后采用线性时变序列逼近方法将非线性系统转化为线性时变系统,通过对线性系统的迭代运算得到非线性系统的最优跟踪控制器,从而实现最优PDF跟踪.理论分析和仿真实验均表明了所提出算法的有效性.  相似文献   

18.
In this paper, globally asymptotical stabilization problem for a class of planar switched nonlinear systems with an output constraint via smooth output feedback is investigated. To prevent output constraint violation, a common tangent‐type barrier Lyapunov function (tan‐BLF) is developed. Adding a power integrator approach (APIA) is revamped to systematically design state‐feedback stabilizing control laws incorporating the common tan‐BLF. Then, based on the designed state‐feedback controllers and a constructed common nonlinear observer, smooth output‐feedback controllers, which can make the system output meet the predefined constraint during operation, are proposed to deal with the globally asymptotical stabilization problem of planar switched nonlinear systems under arbitrary switchings. A numerical example is employed to verify the proposed method.  相似文献   

19.
目前非线性随机系统的控制方法存在设计复杂,计算成本高,以及缺乏稳定性或收敛性证明等缺点,针对这些问题,本文在作者前期研究的基础上发展了一种全新的针对部分可积的非线性随机系统的反馈控制,使得受控系统输出的稳态概率密度逼近事先给定的目标概率密度,并利用Lyapunov函数法证明受控系统的收敛性.数学仿真结果证明了这种方法的可行性和正确性.  相似文献   

20.
针对一类控制方向未知的含有时变不确定参数和未知时变有界扰动的全状态约束非线性系统,本文提出了一种基于障碍Lyapunov函数的反步自适应控制方法.障碍Lyapunov函数保证了系统状态在运行过程中始终保持在约束区间内;Nussbaum型函数的引入解决了系统控制方向未知的问题;光滑投影算法确保了不确定时变参数的有界性.障碍Lyapunov函数、Nussbaum型函数及光滑投影算法与反步自适应方法的有效结合首次解决了控制方向未知的全状态约束非线性系统的跟踪控制问题.所设计的自适应鲁棒控制器能在满足状态约束的前提下确保闭环系统的所有信号有界.通过恰当地选取设计参数,系统的跟踪误差将收敛于0的任意小的邻域内.仿真结果表明了控制方案的可行性.  相似文献   

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