质子交换膜燃料电池容错控制方法综述

质子交换膜燃料电池(proton exchange membrane fuel cell,PEMFC)作为一种高效、环保的能量转换装置,具有广阔的工业应用前景。然而,多辅助系统和运行时涉及多物理场耦合现象的特征,使PEMFC易发生水管理、热管理、反应物饥饿等各类故障,且故障难以控制。为及时有效地消除故障并稳定输出性能、提高耐久性,拥有实时在线特征及诊断精度高等优点的容错控制方法被应用于优化PEMFC的运行。容错控制分为故障诊断和控制重构两部分。该文对基于模型和基于非模型的故障诊断方法进行综述,并总结了各自的优缺点。随后,从结构框图角度介绍控制器调节模块以及决策模块的功能和必要性,并综述了现有研究中容错控制在PEMFC的应用。最后,总结了PEMFC领域现有研究需做出的改进以及容错控制的发展前景。     

基于旋转坐标系IPMSM的容错控制策略研究

针对内置式永磁同步电机(IPMSM),当以旋转变压器为位置传感器发生严重故障时,提出了一种故障诊断及容错的方案。采用了基于旋转坐标系的改进滑模观测器算法和TypeⅡ型跟踪环路转子位置和角速度提取算法,用于IPMSNM的转子位置和角速度的估算。利用估算数据分析并检测位置传感器是否出现故障,并采用加权算法实现故障情况下系统的平滑切换。通过搭建MATLAB/Simulink仿真模型对设计的方案进行验证,输出的结果显示了此方案具有较好的容错控制效果,说明了提出的这个方案可行性和有效性。     

基于卡尔曼滤波理论的容迟与容断网络自适应感知路由算法

针对容迟与容断网络中的单播通信问题,提出了一种自适应感知路由协议(adaptive context aware routing protocol,ACRP);并引入卡尔曼滤波理论,给出最优的消息轮渡节点选取策略.仿真实验表明,与常见的单副本拷贝或多副本拷贝协议相比,提出的面向情境感知的自适应路由协议拥有更好的传输性能和稳定性.     

网口容错在嵌入式设备中的设计与实现

针对嵌入式网络设备的服务可靠性问题,现有的网口容错主要采用双网卡冗余设计,研究针对单网卡多网口的情况,提出了一种网口容错方法,该方法能有效利用系统带宽资源。提出的网口容错方法包括一种网口状态检测机制和故障网口服务数据迁移方法,并设计了相应的功能模块。故障检测模块实现基于Loopback的检测方法,容错处理模块则实现在检测到故障后,可将故障网口的服务负载数据根据迁移策略迁移到其余正常网口。所提出的方法实现了对网口工作状态的快速检测和负载数据的有效容错。该方法具有应用无关性、资源占用率低的特点,通过测试验证了该方法的可行性。     

Adaptive fault tolerant control for a class of input and state constrained MIMO nonlinear systems

In this work, we present a novel adaptive fault tolerant control (FTC) scheme for a class of control input and system state constrained multi‐input multi‐output (MIMO) nonlinear systems with both multiplicative and additive actuator faults. The input constraints can be asymmetric, and the state constraints can be time‐varying. A novel tan‐type time‐varying Barrier Lyapunov Function (BLF) is proposed to deal with the state constraints, and an auxiliary system is designed to analyze the effect of the input constraints. We show that under the proposed adaptive FTC scheme, exponential convergence of the output tracking error into a small neighbourhood of zero is guaranteed, while the constraints on the system state will not be violated during operation. Estimation errors for actuator faults are bounded in the closed loop. An illustrative example on a two degree‐of‐freedom robotic manipulator is presented to demonstrate the effectiveness of the proposed FTC scheme. Copyright © 2015 John Wiley & Sons, Ltd.     

探究用电检查管理中营配信息集成的重要作用

随着我国经济和科学技术的不断发展,用电检查也应从传统的实地管理模式转为自动化、信息化的管理模式。详细阐述、分析了营配信息集成在用电检查工作中的作用。     

Adaptive type-2 fuzzy sliding mode controller for SISO nonlinear systems subject to actuator faults

In this paper, an adaptive type-2 fuzzy sliding mode control to tolerate actuator faults of unknown nonlinear systems with external disturbances is presented. Based on a redundant actuation structure, a novel type-2 adaptive fuzzy fault tolerant control scheme is proposed using sliding mode control. Two adaptive type-2 fuzzy logic systems are used to approximate the unknown functions, whose adaptation laws are deduced from the stability analysis. The proposed approach allows to ensure good tracking performance despite the presence of actuator failures and external disturbances, as illustrated through a simulation example.     

Robust Fault‐Tolerant Control of Launch Vehicle Via GPI Observer and Integral Sliding Mode Control

A robust fault‐tolerant attitude control scheme is proposed for a launch vehicle (LV) in the presence of unknown external disturbances, mismodeling dynamics, actuator faults, and actuator's constraints. The input‐output representation is employed to describe the rotational dynamics of LV rendering three independently decoupled second order single‐input‐single‐output (SISO) systems. In the differential algebraic framework, general proportional integral (GPI) observers are used for the estimations of the states and of the generalized disturbances, which include internal perturbations, external disturbances, and unknown actuator failures. In order to avoid the defects of the conventional sliding surface, a new nonlinear integral sliding manifold is introduced for the robust fault‐tolerant sliding mode controller design. The stability of the GPI observer and that of the closed‐loop system are guaranteed by Lyapunov's indirect and direct methods, respectively. The convincing numerical simulation results demonstrate the proposed control scheme is with high attitude tracking performance in the presence of various disturbances, actuator faults, and actuator constraints.     

CNG加气站爆炸燃烧的交通疏散仿真分析

随着石油资源的日益短缺和国家能源战略的调整,环保要求和汽车技术的不断提高,燃气车辆不断增多,与之相对应的车用加气站的数量也越来越多。但是接连发生的加气站燃气泄漏与火灾事故使得加气站的使用安全问题成为日益关注的问题。当加气站出现燃气泄漏与火灾事故时,天然气未立即着火可形成爆炸气体云团,遇火就会发生爆炸,在危险距离以内,人会受到爆炸冲击波的伤害。重点将对CNG加气站爆炸事故后的交通疏散条件制定分级标准,结合实例采用计算机软件仿真疏散分析,对以后进行新建加气站的安全评估分析工作开展提供定量依据。     

基于改进BP神经网络的道路交通事故预测

道路交通事故因受多种随机因素的影响而呈现出非线性的特点,传统的线性分析方法无法完全揭示其内涵。在分析道路交通事故与人、车、路等因素关系的基础上,利用神经网络具有描述非线性特性的能力,将影响交通事故的多种因素综合起来建立了基于改进BP神经网络的道路交通事故预测模型。选取人口密度、路网密度和机动车辆密度作为交通事故预测模型的输入神经元,采用道路交通综合死亡率作为道路交通事故的输出评价指标,对道路交通事故进行预测。实验结果表明,该预测模型能很好地适用于道路交通事故预测,验证了该模型的可行性和有效性。