Dissipativity-based robust reduced-order fault estimation observer design of multi-agent systems

In this paper, a distributed reduced-order fault estimation observer is studied for both continuous- and discrete-time multi-agent systems with directed communication topologies. Initially, a distributed reduced-order observer is proposed to estimate the occurred faults, which can reduce the number of the fault estimation observer’s order of multi-agent systems. What is more, based on strict dissipativity and pole placement constrains, a multi-constrained design is given to calculate gain matrices of distributed reduced-order observer. Finally, simulation results are presented to demonstrate the effectiveness of the proposed distributed reduced-order fault estimation technique.     

基于模式分析的对称和非对称三相不接地系统故障测距算法研究

基于模式分析理论,提出了不接地三相的两相短路、单相接地和两相接地故障测距 的新算法.计算机仿真和实际电网的模拟故障测距试验表明该算法有效.     

基于虚拟化技术的仿真系统容错优化方法

节点崩溃或者仿真资源不足导致的分布式仿真系统故障,降低了仿真系统可靠性。为保证系统容错效果,降低容错开销,提出了一种基于虚拟化技术的仿真系统容错方法,按照系统故障发生的位置,对不同类型故障动态采用不同类型的容错策略。分析了检查点容错策略的优化方法,给出了最优设置间隔;结合虚拟化技术的优势,解决了副本容错策略的节点选择、副本数量以及位置分布问题;同时,引入基于虚拟机迁移的容错策略,并将其作为检查点容错策略和副本容错策略的补充,以降低容错开销。通过仿真实验数据对比,分析了动态容错策略与普通容错策略的性能,可知动态容错策略保证了系统容错性能,容错开销也保持在较低水平。     

A decoupled federate architecture for high level architecture-based distributed simulation

A number of research issues arise in executing large scale High Level Architecture (HLA) based distributed simulations. Among these issues distributed simulation cloning, fault tolerance and Grid enabled architecture are particularly important and challenging. This paper presents a Decoupled Federate Architecture as the underlying infrastructure to facilitate a solution to each of the above issues.     

分布式计算系统回卷恢复容错的仿真设计

为了解决分布式计算系统回卷恢复容错的验证评估问题,设计一种分布式计算系统的回卷恢复容错算法的仿真机制,依据分布式计算系统回卷恢复容错的总体架构,将分布式计算系统中的节点任务过程使用离散事件模拟,在网络系统仿真工具的应用层增加支持多任务回卷恢复容错仿真的模块,并设计用于回卷恢复容错仿真的结构、功能模块和系统参数设定。结果表明本文提出的仿真机制能够实现分布式计算系统的回卷恢复容错算法的模拟验证,为不同容错算法间对比、改进与优化提供参照。      

面向多径业务传输的快速故障定位机制

为解决WDM光网络中快速准确定位故障的难题,提出一种面向多径业务传输的快速故障定位机制,即建立多径业务传输模型来寻找多条链路分离光通路,在此基础上,各网络节点分布式独立计算故障链路向量,以快速限制定位区域。通过理论分析和仿真表明,所提机制对业务分布依赖性更低,能够迅速实现故障完全定位,并能提升故障定位速度。     

关于链路故障的分布式故障诊断

一、引言 在分布式系统中,故障诊断应包括故障结点机的诊断和故障链路的诊断,故障链路的诊断在分布式系统级故障诊断中占有重要地位,它不仅是分布式乐统级故障诊断的目标,而且也是分布式系统级故障诊断的前提,因为一个系统的链路发生故障,则将会对故障结点机的诊断带来困难。在现有的诊断算法中,并不是所有的诊断算法都考虑了链路故障。 在分布式系统中,虽然任两个结点机之间都能进行通讯,也即都能进行互测,因而实际分布式系统的测试图的拓扑结构可以是任意结构的,但我们一般只在实际分布式系统的拓扑结构是分布式的或多总线的情形下才考虑链路故障。因为在单总线系统中,链路故障的出现将是致命的,会使整个系统的故障诊断成为不可能,因此一般不考虑链路故障。     

On probabilistic diagnosis of multiprocessor systems using multiplesyndromes

This paper addresses the distributed self-diagnosis of a multiprocessor/multicomputer system based on fault syndromes formed by comparison testing. The authors show that by using multiple fault syndromes, it is possible to achieve significantly better diagnosis than by using a single fault syndrome, even when the amount of time devoted to testing is the same. They derive a multiple syndrome diagnosis algorithm that in terms of the level of diagnostic accuracy achieved, is globally suboptimal, but optimal among all diagnosis algorithms of a certain type to be defined. The diagnosis algorithm produces good results, even with sparse interconnection networks and interprocessor tests with low fault coverage. It is also proven that the diagnosis algorithm produces 100% correct diagnosis as N, the number of nodes in the system, approaches ∞, provided that the interconnection network has connectivity greater than or equal to 2 and that the number of syndromes produced grows faster than log N. This solution and another multiple syndrome diagnosis solution by Fussell and Rangarajan (1989) are comparatively evaluated, both analytically and with simulations     

配电网故障区段定位及测距方法

针对配电网发生单相接地故障后采用人工巡线定位故障困难的问题,提出了一种基于分布参数模型的配电网故障区段定位及测距方法。该方法通过对线路上馈线终端装置上传的故障信息及数据进行分析计算,选择故障区段,然后在线计算该区段线路分布参数,从而得出故障距离。仿真结果表明,该方法受过渡电阻和故障位置等因素影响小,能有效实现故障选线和区段定位,测距误差在1%以内。     

Distributed fault diagnosis for process and sensor faults in a class of interconnected input–output nonlinear discrete-time systems

This paper presents a distributed fault diagnosis scheme able to deal with process and sensor faults in an integrated way for a class of interconnected input–output nonlinear uncertain discrete-time systems. A robust distributed fault detection scheme is designed, where each interconnected subsystem is monitored by its respective fault detection agent, and according to the decisions of these agents, further information regarding the type of the fault can be deduced. As it is shown, a process fault occurring in one subsystem can only be detected by its corresponding detection agent whereas a sensor fault in a subsystem can be detected by either its corresponding detection agent or the detection agent of another subsystem that is affected by the subsystem where the sensor fault occurred. This discriminating factor is exploited for the derivation of a high-level isolation scheme. Moreover, process and sensor fault detectability conditions characterising quantitatively the class of detectable faults are derived. Finally, a simulation example is used to illustrate the effectiveness of the proposed distributed fault detection scheme.     

基于智能监控系统的分布式光伏故障自动诊断研究

传统故障诊断方法都是从分布式光伏组件外部特性进行故障判断,对于内部参数的变化缺少观察,导致分布式的故障类型诊断准确率低,因此,设计一种基于智能监控系统的分布式光伏故障自动诊断方法。以两级分布式光伏作为研究对象,建立并网运行的数学模型,通过智能监控系统得到内部参数故障评判特征值,采用崩溃点直接计算的方法计算电压崩溃、越限崩溃约束临界点,最后利用人工鱼群算法优化RBF神经网络,得到光伏自动诊断的算法流程。通过仿真实验结果表明,设计方法对不同故障类型的诊断准确率均高于两种传统方法,验证了设计方法的有效性。     

Distributed sensor fault diagnosis in a class of interconnected nonlinear uncertain systems

In this paper, a distributed sensor fault detection and isolation (FDI) method is developed for a class of interconnected nonlinear uncertain systems. In the distributed FDI architecture, a FDI component is designed for each subsystem in the interconnected system. For each subsystem, its corresponding local FDI component is designed by utilizing local measurements and certain communicated information from neighboring FDI components associated with subsystems that are directly interconnected to the particular subsystem under consideration. Under certain assumptions, adaptive thresholds for distributed sensor fault detection and isolation in each subsystem are derived, ensuring robustness with respect to interactions among subsystems and system modeling uncertainty. Moreover, the fault detectability condition is rigorously investigated, characterizing the class of sensor faults in each subsystem that is detectable by the proposed distributed FDI method. Additionally, the stability and learning capability of the distributed adaptive fault isolation estimators is established. A simulation example of interconnected inverted pendulums mounted on carts is used to illustrate the effectiveness of the distributed FDI method.     

WSN中考虑节点磨损的分布式自稳定网络寿命优化算法

针对无法预估的节点故障影响无线传感器网络寿命的问题,本文提出了一种考虑节点磨损的分布式自稳定优化算法。首先,利用韦伯函数拟合网络生命周期的分布,定期唤醒睡眠节点进行故障检测;然后,采用分布式调度,无需知道传感节点的位置信息,使用多个节点同时工作,从而提高效率;最后,通过较低的网络通信代价,及时使用空闲节点替代故障节点,保持网络的连通性。理论分析和仿真实验验证了本文算法的有效性及可靠性,仿真结果表明,当传感器节点的可靠性随着使用时间与磨损下降时,本文算法可以更好地延长无线传感器网络寿命,相比分布式多目标概率覆盖协议,本文算法在寿命延长、覆盖率、节点唤醒次数等方面均取得更好的性能。     

Cluster环境中多Agent系统分布仿真的容错技术

随着网络的普及和个人计算机性能的提高,需要能够在网络Cluster环境下进行多Agent系统的仿真。而如何防止Cluster环境中个别结点的失效导致全系统仿真的失败,是Cluster环境中进行分布仿真的重要研究领域。本文提出了一种适合于网络Cluster环境的多Agent分布仿真体系结构和具有容错机制的分布并行仿真算法,并已成功应用到复杂系统分布仿真平台上。     

一类互联非线性系统的分布式故障估计观测器设计

针对一类互联非线性系统,提出一种分布式故障估计观测器设计方法.首先,将状态向量和故障向量进行增广设计,得出等价的增广互联系统;其次,利用互联子系统之间的耦合信息,设计包含关联子系统估计信息的分布式故障估计观测器,用于在线实时估计子系统中出现的故障;再次,提出基于$H_\infty$性能和$L_2-L_\infty$性能的方法求解观测器增益矩阵;最后,通过一个仿真实验表明所提出方法的可行性和有效性.     

基于Agent的复杂系统分布仿真中的容错研究

分布仿真已经成为研究复杂系统的有效方法之一，为了提高仿真效率，保证在结点或网络出现故障的情况下，不会导致整个仿真应用重新开始，需要在仿真框架中加入容错措施，在该文中以一般分布式系统中的容错技术为指导，结合分布仿真算法，对基于Agent分布仿真系统中容错机制进行了研究。     

关于并行随机数发生器的若干算法

１．引 言 随机数发生器是 Ｍｏｎｔｅ Ｃａｒｌｏ模拟方法的最基本工具．并行计算机的出现和发展,为并行 Ｍｏｎｔｅ Ｃａｒｌｏ方法的研究提供了有力的工具．Ｍｏｎｔｅ Ｃａｒｌｏ方法本身具有很强的并行性,但是,要把在串行计算机上使用Ｍｏｎｔｅ Ｃａｒｌｏ方法程序移植到并行计算机上运行,首先就需要解决随机数发生器的并行化问题．针对各类不同的并行计算机结构,可以构成不同的并行随机数发生器的算法． 乘同余发生器是应用最广泛的随机数发生器之一,无论是在串行计算机上,还是在并行计算机上都具有极大的影响和深人的应用．…     

基于遗传粒子群法的配电网故障定位研究

针对分布式电源接入后配电网故障定位困难的现状,构造了适应多分布式电源接入的故障电流编码方式、开关函数和评价函数。提出了基于改进遗传粒子群法的配电网故障定位方法,该方法有效融合了遗传算法在全局搜索方面和粒子群法在局部搜索方面的优势。建立配电网故障定位仿真实例,通过配电网系统单重故障和多重故障及FTU上传故障信息出现畸变情况的仿真对比分析,结果表明本方法具有更高的定位准确率和较快的收敛速度,且本方法抗干扰性更强。本研究成果可为配电网故障定位提供有效的参考和技术指导。     

分布式并行系统中的一种故障分类模型

故障诊断是分布式并行环境下容错系统的关键部分,故障分类模型是影响故障诊断性能的重要因素之一。由于不同的分布式系统有其不同的特点．为了减少系统在故障诊断方面的负担,故障诊断方案一般都考虑程序的需求和系统的属性,选择最合适的故障分类模型。本文提出了一种新的分布式并行环境下的故障分类模型,可以将故障诊断限定在一个合理的故障集中。将这种分类模型和特殊的程序需求以及系统属性相结合,能够得到一个效果理想的故障检测方案。