基于超声波的纸页挺括性检测方法研究

分析了纸页挺括性的特征以及超声波用于无损检测的原理,提出了一种利用超声波检测纸页挺括性的方案,设计并实现了基于超声波的纸页挺括性的检测系统。以收据、书本纸、打印纸为例,实验得到了它们对超声波的衰减特性。结合纸样的实验结果,分析挺括性指标能体现出纸页在抄造过程和质量方面存在的问题,对改进纸页的质量具有重要的参考价值。     

纸页定量工业过程智能控制器

针对纸页定量这种具有大时滞系统的控制问题，提出了一种利用几种控制算法进行了分区决策的新型控制器结构，仿真研究证明了控制器的有产性。     

用工控机实现纸机干燥部热泵供热系统控制

介绍一种基于工控机的纸页干燥控制系统,叙述了热泵供热系统的构成有原理。还介绍了测控系统功能,系统硬件、软件配置。     

纸页定量的智能自校正控制

本文针对自校正调节器应用于纸页定量控制所存在的问题提出了一种智能自校正控制方案，这种控制方案既保留了自适应控制适应过程参数变化的特点，又提高了控制系统的稳定鲁棒性，仿真计算证明了本文结果。     

基于变化率模型的滑模变结构控制及应用

滑模变结构控制具有响应快速、对参数及外界扰动不灵敏的特点。具有代表性的趋近律等设计方法大都需要对象的数学模型,工程应用受到一定限制。对此,提出一种基于被控变量变化率模型的滑模变结构控制方法,以系统偏差和偏差变化率为状态变量建立切换函数,根据变化率模型设计等效控制作用,根据切换函数与系统正反特性设计切换控制作用,同时对滑模变结构控制算法进行改进以减弱抖振。该控制策略无需对象的严格数学模型,工程上容易实现。通过经验测试法建立了聚丙烯反应釜仿真对象温度的变化率模型,基于该模型设计的滑模变结构控制取得了优良的控制效果,验证了控制方案的可行性与有效性。     

电子信息系统中的印章功效

在将传统的纸页信息处理过程搬移到电子信息处理平台时,人们开始关注纸页印章(签名)的作用在电子政务系统中如何保持。目前,有的人和一些企业正在研究并推出所谓“电子印章系统”的概念及产品。政府有关部门也准备推动这一新技术的应用。那么如何认识纸页印章体制的作用,是不是在以电子方式处理信息的环境里一定也要有     

火电厂煤粉锅炉结构分散化模型

本文根据链系统方法,建立了火电厂煤粉锅炉结构分散化模型,该模型以子系统模型给出,显含整体系统的因果结构。     

多媒体共享教学系统的开发模型与实现

提出了一种基于计算机网络、智能中央控制设备,实现控制中心和教室多级协同控制的多媒体共享教学系统的方案.介绍了多媒体共享教学系统的工作原理,并进一步给出了系统的开发模型与实现方法,该系统是一种新颖的多媒体教室方案.     

多媒体共享教学系统的开发模型与实现

提出了一种基于计算机网络、智能中央控制设备，实现控制中心和教室多级协同控制的多媒体共享教学系统的方案。介绍了多媒体共享教学系统的工作原理，并进一步给出了系统的开发模型与实现方法，该系统是一种新颖的多媒体教室方案。     

自适应神经变结构的机器人轨迹跟踪控制

提出一种神经网络与变结构融合的控制策略用于非线性机器人控制,该方案利用神经网络来自适应补偿不确定模型,并通过变结构控制器消除逼近误差.考虑到局部泛化网络的不足,根据其状态空间的划分,分别对3个区间采用神经网络与变结构的分级与集成控制.该方案能在控制阶段初期及网络逼近区域外使两种控制器共同起作用以保持系统的强鲁棒性,基于Lyapunov理论证明了闭环系统的全局稳定性.仿真结果进一步表明了该方法的优越性.     

Decentralized Resilient H∞ Load Frequency Control for Cyber-Physical Power Systems Under DoS Attacks

This paper designs a decentralized resilient H_∞ load frequency control (LFC) scheme for multi-area cyber-physical power systems (CPPSs). Under the network-based control framework, the sampled measurements are transmitted through the communication networks, which may be attacked by energy-limited denial-of-service (DoS) attacks with a characterization of the maximum count of continuous data losses (resilience index). Each area is controlled in a decentralized mode, and the impacts on one area from other areas via their interconnections are regarded as the additional load disturbance of this area. Then, the closed-loop LFC system of each area under DoS attacks is modeled as an aperiodic sampled-data control system with external disturbances. Under this modeling, a decentralized resilient H_∞ scheme is presented to design the state-feedback controllers with guaranteed H_∞ performance and resilience index based on a novel transmission interval-dependent loop functional method. When given the controllers, the proposed scheme can obtain a less conservative H_∞ performance and resilience index that the LFC system can tolerate. The effectiveness of the proposed LFC scheme is evaluated on a one-area CPPS and two three-area CPPSs under DoS attacks.      

具有不确定未知界的相似组合系统的鲁棒自适应跟踪控制

讨论一类具有相似结构的不确定组合系统的鲁棒自适应跟踪问题。针对系统的不确定性界和扰动界完全未知的情形，首先从理论上证明了可设计鲁棒自适应分散跟踪控制器，确保受控系统的输出渐近跟踪参考模型的输出；进而从工程实际的角度，给出了确保受控系统输出实用跟踪参考模型输出的鲁棒自适应分散跟踪控制器的设计方案。     

Decentralized robust controller design for a class ofinterconnected uncertain systems: with unknown bound of uncertainty

In this paper, a simple decentralized robust control scheme is proposed for a class of interconnected time-varying systems with uncertainties. The uncertainties may appear in the interconnections between the subsystems and also within the subsystems, and they are possibly nonlinear and time-varying. The uncertainties are bounded, but the bounds of the uncertainties are unknown in controller design. When certain matching conditions are satisfied for the uncertain interconnections and the uncertainties within the subsystems, the proposed decentralized control scheme guarantees the controlled system to converge exponentially with a prescribed degree toward the equilibrium of the system, or a residual ball around the equilibrium     

Decentralized robust control of multiple static var compensators via Hamiltonian function method

Using the energy-based Hamiltonian function method, this paper investigates the decentralized robust nonlinear control of multiple static var compensators (SVCs) in multimachine multiload power systems. First, the uncertain nonlinear differential algebraic equation model is constructed for the power system. Then, the dissipative Hamiltonian realization of the system is completed by means of variable transformation and prefeedback control. Finally, based on the obtained dissipative Hamiltonian realization, a decentralized robust nonlinear controller is put forward. The proposed controller can effectively utilize the internal structure and the energy balance property of the power system. Simulation results verify the effectiveness of the control scheme.     

分散模型参考自适应控制

本文针对由参数未知、存在有界扰动和非线性关联的子系统组成的大规模互联系统,提出 了一种新的分散模型参考自适应控制法.它适用于孤立子系统传递函数的相对阶次n*i为任 意值的情况.根据李雅普诺夫稳定性理论,文中证明了这种分散自适应控制系统全局稳定的 充分条件.与有关文献所介绍的方法相比,本文的方法可用于n*i>2的场合,因而它更具有 一般性和实用性.     

Decentralized adaptive control scheme for control of a multi-arm-type robot

This paper deals with the problem of decentralized stabilization for a class of unknown large-scale dynamic systems formed of interconnected subsystems under constant disturbances. A decentralized adaptive control scheme is proposed based on the Lyapunov direct method and a condition of asymptotic stability is derived. Then the decentralized adaptive control scheme is applied for a class of robot manipulators to track the desired trajectory as closely as possible despite a wide range of manipulator motions and parameter uncertainties of links and payload.     

Adaptive neural decentralized control for strict feedback nonlinear interconnected systems via backstepping

An approximation based adaptive neural decentralized output tracking control scheme for a class of large-scale unknown nonlinear systems with strict-feedback interconnected subsystems with unknown nonlinear interconnections is developed in this paper. Within this scheme, radial basis function RBF neural networks are used to approximate the unknown nonlinear functions of the subsystems. An adaptive neural controller is designed based on the recursive backstepping procedure and the minimal learning parameter technique. The proposed decentralized control scheme has the following features. First, the controller singularity problem in some of the existing adaptive control schemes with feedback linearization is avoided. Second, the numbers of adaptive parameters required for each subsystem are not more than the order of this subsystem. Lyapunov stability method is used to prove that the proposed adaptive neural control scheme guarantees that all signals in the closed-loop system are uniformly ultimately bounded, while tracking errors converge to a small neighborhood of the origin. The simulation example of a two-spring interconnected inverted pendulum is presented to verify the effectiveness of the proposed scheme.     

Design of decentralized robust load-frequency controller based on SVD method

A decentralized robust control scheme is presented for the load-frequency control of interconnected power systems with uncertain parameters. A singular value decomposition (SVD) technique and Lyapunov stability theory are adopted to implement a decentralized robust controller. The stability analysis of the closed-loop interconnected systems for all admissible uncertainties is discussed. The performance robustness of the proposed decentralized robust control scheme has been verified through simulation studies on a two-area power system model. The effectiveness of the decentralized control algorithm is compared to that of a centralized robust one. It has been found that both control schemes have almost the same performance with integral control action in the presence of parametric uncertainty in the plant.     

H∞ decentralized fuzzy model reference tracking controldesign for nonlinear interconnected systems

In general, due to the interactions among subsystems, it is difficult to design an H_∞ decentralized controller for nonlinear interconnected systems. The model reference tracking control problem of nonlinear interconnected systems is studied via H_∞ decentralized fuzzy control method. First, the nonlinear interconnected system is represented by an equivalent Takagi-Sugeno type fuzzy model. A state feedback decentralized fuzzy control scheme is developed to override the external disturbances such that the H∞ model reference tracking performance is achieved. Furthermore, the stability of the nonlinear interconnected systems is also guaranteed. If states are not all available, a decentralized fuzzy observer is proposed to estimate the states of each subsystem for decentralized control. Consequently, a fuzzy observer-based state feedback decentralized fuzzy controller is proposed to solve the H_∞ tracking control design problem for nonlinear interconnected systems. The problem of H _∞ decentralized fuzzy tracking control design for nonlinear interconnected systems is characterized in terms of solving an eigenvalue problem (EVP). The EVP can be solved very efficiently using convex optimization techniques. Finally, simulation examples are given to illustrate the tracking performance of the proposed methods     

New overlapped decentralized controller for large-scale systems

This paper is devoted to the development of a new decentralized control approach for large-scale interconnected dynamical systems. The proposed decentralized control structure is based on the concept of overlapping decomposition. The controller gains for the overlapped subsystems are calculated only once and they are easy to compute since all operations are carried out at the subsystems level. Since the proposed decentralized controller operates under a completely decentralized information pattern, the inaccessible states for each augmented subsystem are estimated using a set of overlapped decentralized estimators. A sufficient condition is developed for the stability of the global system with the decentralized control scheme subject to structural perturbations. It is shown that with the satisfaction of this condition, the proposed controller provides a robust design which is insensitive to structural perturbations.