"小触大"控制系统在机组改造中的应用实践

本文主要介绍了“小触大”控制系统在机组改造中的方案及其成功应用,说明了老式机组改造巨大的节能前景。     

PLC 在大电流整流机组控制保护系统中的应用

分析了大电流整流机组中保护、控制电路中存在的问题。以及可编程控制器取代继电器保护、控制系统的可行性和优越性，介绍了PLC保护、控制系统的硬件设计与配置。PLC程序设计。以及应用效果。     

Distributed event-triggered cooperative attitude control of multiple rigid bodies with leader–follower architecture

In this note, the distributed event-triggered cooperative attitude control of multiple rigid bodies with leader–follower architecture is investigated, where both the cases of static and dynamic leaders are all considered. Two distributed triggering procedures are first introduced for the followers and leaders, and then the distributed cooperative controllers are designed under the proposed triggering schemes. Under the designed controllers with the event-triggered strategies, it is shown that the orientations of followers converge to the convex hull formed by the desired leaders’ orientations with zero angular velocities. Moreover, the communication pressure in network is reduced and the energy of each agent is saved. Simulation results show the effectiveness of the proposed method.     

Probabilistic‐constrained filtering for a class of nonlinear systems with improved static event‐triggered communication

This paper is concerned with the probabilistic‐constrained filtering problem for a class of time‐varying systems with stochastic nonlinearities and state constraints. An improved static event‐triggering scheme is used to reduce unnecessary signal transmissions on the communication channel, where a time‐varying triggering parameter is designed according to engineering practice. The aim of the problem addressed is to design a time‐varying filter such that (1) the prescribed probabilistic constraints on the estimation error are satisfied (ie, the probability for the estimation error to be confined to the given ellipsoidal set is larger than a prescribed value) and (2) the ellipsoid is minimized at each time instant in the sense of the matrix norm. First, the probabilistic constraints are handled by means of the multidimensional Chebyshev bounds. By using recursive matrix inequalities, stochastic analysis is conducted to establish sufficient conditions for the existence of the desired probabilistic‐constrained filter. Then, a recursive optimization algorithm is proposed to design the filter gain matrices. Finally, a simulation example is proposed to demonstrate the effectiveness and applicability of the proposed method.     

基于双向图算法的快速部分汉语语法分析器

本文给出了一个用双向图算法实现的快速部分汉语语法分析器。为了实现真实文本的快速部分语法分析，分析器使用ＦＩＲＳＴ分析表和ＬＡＳＴ分析表来更大程度地避免创建不必要的活动弧，并且引进了弧的竞争机制和对于一些情况的处理方法，使用了各种分析策略的分析器的准确率达到８７．２％，在主频６６ＭＨｚ的４８６机型上运行速度是３２句／分。     

基于观测器的周期拒绝服务攻击网络化系统动态事件触发控制

针对具有周期拒绝服务(DoS)攻击的网络化系统,设计一种基于观测器的具有动态事件触发策略的控制器.首先,通过DoS攻击对网络化系统的影响建立了DoS攻击模型,采用切换系统的方法,将具有DoS攻击的网络化系统分为DoS攻击活跃子系统和DoS攻击休眠子系统.对不可测的系统状态设计状态观测器,通过在静态事件触发中引入一个内部...     

Event‐triggered output consensus for heterogeneous multiagent systems with fixed and switching directed topologies

This paper studies the event‐triggered output consensus problem of heterogeneous linear multiagent systems characterized via fixed and switching directed graphs. With proper state‐dependent triggering functions, two new event‐triggered output consensus control schemes are proposed for each agent to achieve consensus. Notably, under the proposed control protocols, continuous communication among agents is not required in both controllers updating and triggering threshold detection, which means being completely continuous communication free. The communication instances are reduced significantly, and the periodic or high‐frequency communication is restrained. It is also ensured that events cannot be triggered infinitely in finite time (ie, the Zeno behavior is elegantly avoided). Meanwhile, the simulation examples are given to illustrate the theoretical analysis.     

‐Gain analysis of event‐triggered networked control systems: a discontinuous Lyapunov functional approach

In this paper, the problems of exponential stability and ‐gain analysis of event‐triggered networked control systems (NCSs) with network‐induced delays are studied. We first propose event‐triggering conditions in the sensor side and controller side, respectively. Because the implementation of our event‐triggering scheme only needs periodic supervision of the system state at the constant sampling instants, instead of being monitored continuously, it is expected that the scheme will improve the resource utilization. Taking the network‐induced delays into account and using delay system approach, we constructed a unified model of NCSs with hybrid event‐triggering schemes. On the basis of this model, sufficient conditions for the exponential stability and ‐gain analysis are developed in the form of LMIs by using a discontinuous Lyapunov–Krasovskii functional approach. Moreover, the corresponding results can be further extended to more general cases, where the system matrices of the considered plant contain parameter uncertainties, represented in either polytopic or norm‐bounded frameworks. In addition, as a special case, we also present the exponential stability, ‐gain analysis, and the control feedback gain design of event‐triggered NCSs without considering the effects of network‐induced delays and event‐triggering condition in the controller side. Finally, a simulation example is provided to illustrate the usefulness and effectiveness of the proposed hybrid event‐triggering schemes.Copyright © 2012 John Wiley & Sons, Ltd.     

晶闸管强触发电路设计

为了研究晶闸管在强触发下的导通特性,利用功率MOSFET的快开通特性和通流能力,设计了光纤控制晶闸管强触发电路。该电路中晶闸管门极触发电流峰值范围为0.35～39.6 A,前沿范围为35～540 ns,电流上升率范围为3.4～83.3 A/μs。实验结果表明,该电路参数调节范围宽,触发电流抖动小(小于4 ns),具有较高的稳定性和可靠性。     

基于概率触发的负载均衡区域竞选分簇算法

无线传感器网络中由最大连通度生成簇算法得到的簇结构,各簇头节点间负载不均衡,能量消耗较快。对止,用剩余能量和发射功率构建综合权值来决定节点竞选簇头的可能性,并通过设计的拓扑维护概率适当性的对网络拓扑进行局部调整,形成了基于概率触发的负载均衡区域竞选分簇算法,有效地延长了网络生命期。