共查询到20条相似文献，搜索用时 173 毫秒
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电力变压器是电力系统中主要设备之一,在电力系统中占据着重要的地位,由于它结构复杂部件繁多,对其故障原因难以进行分析,提出一种基于故障树的变压器故障诊断专家系统,分析了基于故障树分析的知识获取的过程和知识表示的方法,为变压器故障诊断的进一步的研究打下基础。 相似文献
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为了保证电梯系统的安全稳定运行和故障的精确定位,以现场采集数据信号为基础,采用两层集散式结构框架,构建基于故障树分析的电梯故障诊断专家系统,实现对电梯系统故障的实时诊断和精确定位,保证电梯系统的长期、安全稳定的运行,提高电梯系统的使用寿命。 相似文献
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粗糙集理论在变压器故障诊断专家系统中的应用研究 总被引：7，自引：0，他引：7
在传统的变压器故障诊断专家系统的基础上，为解决专家系统较难获取完备知识的瓶颈问题，提出了一种基于粗糙集理论的故障诊断专家系统。该系统从历史故障数据所形成的决策表出发，运用粗糙集理论进行约简，构建专家系统知识库模型。通过计算诊断规则粗糙度，确定诊断规则的置信程度。利用推理机和故障事例库，实现对知识库的动态维护。 相似文献
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基于故障树分析法建立专家系统有利于知识库的建立和扩充,为拖拉机复杂系统故障源的搜寻提供了一种有效的途径。拖拉机故障诊断专家系统通过＂最小割集＂将故障树与专家系统知识库联系起来,应用相关算法实现故障树的建立、故障树的BDD图转换、BDD图的定性分析和定量分析等,并通过＂规则框架法＂实现推理机过程,验证了故障树专家系统设计的可行性。 相似文献
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在现代经济和科技的不断发展之下，各类新技术层出不穷，对现代企业的发展起到了良好的推动作用。本文就应用Step7实现PLC模块的在线监控进行分析，进而对在线诊断中的基本应用方法、模块诊断符号等进行介绍。此外，结合故障处理组织块功能的介绍，分析相应的故障处理方法，并着重对分布式PLC系统中的相应通讯故障进行分析。以期通过本文的介绍和研究，对应用西门子Step7对PLC系统设备的故障诊断有所启示。 相似文献
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《Journal of The Franklin Institute》2022,359(7):3291-3312
Multiplicative faults generally refer to the change of process parameters or structures which are well-suited to represent the process-related anomalies. Unlike sensor faults and external disturbances that are added into process observations and independent with process states, process-related faults directly influence process states such that it is more challenge to reconstruct and diagnose. To address the process-related fault diagnosis, an online fault reconstruction method based on the multiplicative fault model is proposed with the commonly used multivariate statistical process monitoring framework. The fault reconstruction strategy based on the multiplicative fault representation is given by minimizing reconstruction errors. The diagnosability of the proposed reconstruction method is guaranteed for the change of a single parameter, also known as a unidimensional fault. Moreover, the reconstruction-based contribution is derived for providing heuristic references when diagnosing multidimensional faults. Experiments on a numerical example and a simulated continuous stirred tank heater process benchmark are carried out to investigate the effectiveness of the proposed method. The results show that this method can accurately diagnose the faulty variable or loop and further reconstruct the faulty samples into normal ones. 相似文献
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Until comparatively recently the purification of sea or brackish water depended largely on some form of distillation. In recent years, however, a number of industrial concerns have directed increasing attention to processes depending on reverse osmosis. A number of large plants have been installed and this article reviews the present state of reverse osmosis technology and the factors determining its efficiency. Its advantages include its relatively low fuel consumption, and in this respect further substantial savings are in prospect. 相似文献
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针对机载航空相机补偿板自身特性所造成的故障诊断繁琐、费事、效率低等实际l『口]题,采用蚁群策略,设计出航空相机补偿板故障诊断系统;参考所建立的补偿板故障树模型,确定补偿板的最优故障诊断次序,设计了故障诊断系统的软硬件,理论分析与实践检测结果均表明所设计补偿板故障诊断系统具有快速、可靠的特点,适用于其他航空电子设备系统的故障诊断类问题的解决。 相似文献
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现代伺服系统规模庞大,结构复杂,且通常工作环境恶劣,故障发生率高,故障诊断费时费力。为了提高伺服系统故障诊断定位效率,基于故障树分析和虚拟仪器技术相结合在LabView软件平台上开发了伺服故障诊断定位系统。设计了一种基于最小割集表示的等价故障树的,结合模拟退火粒子群算法对神经网络的训练进行优化,使其故障诊断定位响应时间和准确度都显著提高。最后实验证明所设计系统采用的分析算法能够快速准确的进行故障诊断定位,对故障诊断定位技术的发展具有一定的参考和实际意义。 相似文献
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This paper presents a trajectory-based online control reconfiguration mechanism against unknown fault occurring in an electric circuit. First, we demonstrate the modeling of an electric circuit by taking the time-trajectory viewpoint, where no a priori input–output partition has been made. The uniqueness of this viewpoint lies in the fact that it deals only with variables that describe the system without any dedicated (external or internal -type) representation. Subsequently, we illustrate a novel real-time fault-tolerant control (FTC) strategy based on this trajectory standpoint, which does not require an explicit model-based fault diagnosis unit. Instead, the controller is reconfigured directly based on the trajectories generated by the system in real-time, and the given control specifications. In this way, we efficiently excrete the shortcomings that are often seen in model-based fault-tolerant systems. The proposed FTC method is effectively demonstrated on an RLC circuit. 相似文献
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核能反渗透海水淡化缓解华北水资源危机的作用分析 总被引：3，自引：0，他引：3
华北水资源2050年将产生严重危机,缺口高达520×108m3,除了节水、远程调水之外,还应注意控制人口增长。计算表明,海水淡化可补充15亿方（占总缺口的3%）,也应作为缓解华北水资源危机的有效措施,主要目的是拉动经济增长。在几种大型海水淡化技术中反渗透法较优,其能耗可以通过建3座2×600MW核电站解决,从而优化了华北地区的电源结构,补上了3525MW的电力缺口,为本区经济的快速发展提供了有力保障。核能反渗透海水淡化可以创造一系列新的经济增长点,保护了环境,节约了煤炭、石油、天然气等资源,开发利用了海洋资源,具有深远的可持续发展意义。多效蒸馏的多项技术和经济指标都不如反渗透,并且由于200MW低温核供热堆堆型容量的限制,核能多效蒸馏的经济性不如核能反渗透。 相似文献