基于神经网络的关联规则在故障诊断中的应用

采用加权关联规则算法对设备历史数据库进行挖掘,建立加权关联规则模式库。设备监控数据通过与模式库匹配,实现设备故障诊断。同时,针对钢铁企业中液压设备的特殊性,提出利用自组织竞争神经网络模型确定权值,即将设备故障信息的3个主要属性:重要程度、易损程度、故障等级作为模型的输入,通过训练样本确定设备故障的加权关联规则的权值。实例证明了该方法的有效性。     

基于数字孪生的复杂矿用设备预测性维护系统

针对恶劣工况环境下复杂矿用设备状态监测与预测性维护困难等问题,结合状态监测、故障预警和预测维护等多种综合建模与分析预测技术,提出了一种基于数字孪生的预测性维护系统。首先,介绍了复杂矿用设备数字孪生体的设计流程与构建原理,并在搭建数字孪生体的过程中实现了预测性维护系统的功能;然后,研究了基于LabVIEW、MySQL和Unity3D的状态数据获取方法,利用Unity3D开发引擎搭建了三维可视化复杂矿用设备状态监测平台,并通过虚拟空间可视化展示设备当前状态;最后,分析了优化BP（back propagation,反向传播）神经网络在复杂矿用设备故障预警中的适用性,同时利用MATLAB软件建立了复杂矿用设备关键零部件的预测性维护模型,并将预警结果通过MySQL数据库传输至Unity3D开发引擎,以驱动和部署预设维护流程,实现设备状态实时监测下的关键零部件故障预警。根据采煤机液压系统的实际维修流程,制定了混合现实（mixed reality, MR）预测性维护策略,并以采煤机摇臂部液压柱塞泵为实验对象开展有效性验证。结果表明,所构建的预测性维护系统的故障预测准确率高于90%,且故障预警结果可驱动HoloLens眼镜实现虚拟指导的维修交互,验证了该系统预测性维护功能的有效性。研究结果可为复杂矿用设备的预测性维护提供新思路。     

基于分形理论的自动舵液压阀故障诊断方法研究

针对自动舵液压阀工作过程中存在的非线性问题,提出一种以阀芯位移信号分形特征为判据的故障诊断方法,并研究了分形特征参数——关联维数的计算方法和参数的选择。在建立液压阀数学模型的基础上,对液压阀正常和故障进行仿真,通过确定时间延迟、嵌入维数和无标度区,计算阀芯位移数据的关联维数。结果表明:不同状态的关联维数值具有明显的可分性,可以定量表征液压阀的工作状态,进而达到装备故障诊断的目的。     

大型液压阻尼器仿真建模及静动态性能试验研究

液压阻尼器是一种对速度反应灵敏的振动控制装置,具有抗冲击和减振性能,被广泛使用在核电厂中来支撑主设备.大型液压阻尼器的正常运行对保证核电厂的安全运行有着重要意义.本研究借助(Advanced modeling en-vironment for performing simulation of engineering s...     

Application of Ferrography to Fault Diagnosis of Hydraulic Systems

This paper deals with research on the successful use of ferrography as a wear measurement method for condition monitoring and fault diagnosis of hydraulic sistems.The analysis program and progression is discussed,and a case study for condition monitoring and fault diagnosis of hydraulic systems by means of ferrographys is also reviewed.     

嵌入式Linux在液压系统的状态监测与故障诊断中的应用

针对国产地下无轨采矿设备液压系统故障率高,而其检测和故障诊断手段落后的背景,本文提出了一种基于嵌入式Linux的多传感器信息的液压系统状态监测与故障诊断的设计方案,通过该系统能实时地、可靠地跟踪地下无轨采矿设备液压系统的工作状态,并能将设备运行状态发展趋势、故障信息通过友好的人机界面反映出来。     

基于AHP-TOPSIS方法的智能液压设备设计评价研究

目的 为解决智能液压设备设计方案评价主观片面的问题,优选最佳设计方案。方法 根据问卷调研和专家意见初步构建智能液压设备评价指标,建立智能液压设备设计方案评价模型。采用AHP层次分析法从外部形象、生产成本、人机工程、安全可靠4个方面建立4个准则层指标,12个子准则层指标,并通过计算得到各级指标的最终权重结果及排序;再利用TOPSIS逼近理想解排序法对3款四柱永磁粉末液压设备的设计方案进行评价,计算得到贴近度优劣排序,从而确定最优选方案。结论 通过AHP-TOPSIS相结合的定性定量评价方法,评估出最符合企业需求的四柱永磁粉末液压设备设计方案,为四柱永磁粉末液压设备及同类智能液压设备的设计实践和评价提供参考。     

某型导弹发射装置液压元件故障的预测

阐述某型导弹发射装置液压元件故障预测系统的总体设计思想。确定了监测对象,选取故障特征信号,并从故障特征信号中提取了故障特征参量。介绍了以DAQ系统为硬件平台的系统硬件设计和以LabVIEW8.0为软件开发平台的系统软件设计。应用基于支持向机的故障预测方法实现对发射装置液压元件的故障预测。     

基于Web的远程设备状态监测与交互式维护

虽然现在有许多成功的基于Web的应用，但是专门为设备维护设计的基于Web的系统很少。一个主要的原因是开发这样一个系统存在许多困难，因为它包括大型数据库、信号处理和设备监测和控制的实时数据通信。更重要的是同时具有设计基于Web虚拟仪器和故障诊断经验的专家很少。然而，基于Web的虚拟仪器的益处时明显的，用于设备监测和分析的昂贵硬件仪器可以被低廉的基于软件的虚拟仪器代替。通过在Internet服务器上安装虚拟仪器，当前用于工厂的冗余仪器可以精简到最小。因为每种虚拟仪器只有一套拷贝安装在服务器上，所以维护工作变得简单。通过Web的交互式维护变得容易。本文给出了这样一套基于W eb的维护系统的设计框架。它包括：远程数据传感和记录，采用虚拟仪器的信号处理与分析、智能故障诊断、以及Web交互式维护平台。     

一起制冷压缩机事故分析

工作中要严格执行操作人员持证上岗制度,制冷设备维修人员在故障判断方面要认真仔细,一定做到故障判断准确,否则容易出现更大的事故.     

Two-layer model of equipment fault propagation in manufacturing system

Equipment fault is a major factor that affects the reliability of manufacturing systems. Fault source identification and propagation path search are primary means to reduce and eliminate equipment faults. To this end, this paper proposed a two-layer model of equipment fault propagation in a manufacturing system. One layer, modeled by a small-world network, is a network of parts for a single equipment device. The other, represented by the production relationships of the manufacturing process, is a network of equipment devices for a manufacturing system. Hence, the propagation path of an equipment fault is divided into physical propagation inside a single equipment device and flow propagation within the manufacturing process. The intensity of physical propagation is given by the product of the fault load and the propagation probability between fault nodes within a single equipment device, whereas the flow propagation intensity is equivalent to the yield loss of the manufacturing system due to equipment fault. Therefore, the total intensity of fault propagation in a manufacturing system is given by the product of these two intensities. Subsequently, the ant colony algorithm is used to find the propagation paths with the maximum intensity. Finally, the proposed method is verified using an example of a camshaft manufacturing system.     

非线性复合FSVM在设备故障诊断中的应用

为了提高设备故障诊断的精度和准确性,利用模糊支持向量机（fuzzy support vector machine,FSVM）,处理设备故障样本中的噪声数据。单个核函数构成的FSVM可以处理单一特征的样本集,但不能满足现有设备故障分析实际应用的需求。本文在现有核函数的基础上,进行复合核函数构建,可以有效解决设备故障样本集异构和分布不规则的特征,并可以对于故障进行有效分析,得到较为诊断准确的研究结果。通过对滚动轴承故障实验数据的分析,证明基于复合核函数的FSVM方法,可以有效提高故障诊断的准确度。该方法相比传统FSVM的分析结果,其故障数据信息利用更加充分,故障诊断准确性有效提高,具有较好的有效性和可行性。     

现代自由锻造装备技术研究现状与发展趋势

锻件制造业是国家装备制造业的基础,锻造装备技术是提高锻件质量和生产效率,降低制造成本的必要条件。介绍了现代自由锻造装备,包括自由锻造油压机、锻造操作机和径向锻造油压机的技术特点及发展现状;论述了现代自由锻造装备机械本体结构设计与优化,以及电液控制技术领域的研究进展;对现代自由锻造装备的发展方向进行了展望。     

基于模型比较的液压伺服作动器故障监控仿真研究

针对某型液压伺服作动器,提出一种基于模型比较的方法实现故障监控。阐述了该型作动器的组成及工作原理,之后对其故障模式进行分析,采用基于模型比较的监控方法建立液压伺服作动器的数学模型和仿真模型,运用Matlab软件进行仿真验证,证明本文建立的仿真模型可靠,与实际状态接近程度高,为液压伺服作动器的故障监控提供了可靠依据。     

振动监测技术在旋转机械故障诊断中的应用

随着旋转设备结构复杂程度的提高,其故障发生的几率也随之增加,对故障检测技术要求更高。通过对机械设备振动信号的分析判断故障特征及部位,是旋转机械故障诊断主要手段。文章首先对振动监测技术的原理及典型振动故障的表现形式进行介绍,并利用振动监测技术,举例说明振动监测技术在旋转机械故障诊断中的应用。     

基于液压泵复数信号的log-SAM故障诊断方法研究

针对基于液压泵单源振动信号易受噪声污染、无法有效表征故障特征信息的问题,提出了一种基于复数信号的log-SAM新方法。在液压泵端盖同一截面上,采集两个互相正交传感器上的振动信号;基于全矢思想,对上述双源信号融合为一个复数信号;利用log-SAM对复数信号进行包络分析,充分地突出故障特征信息,抑制噪声干扰;基于总体和最优诊断结果,实现故障诊断分析。通过分析实测液压泵滑靴磨损故障信号可知,所提方法具有很好诊断效果,且较传统全矢谱、基于单源信号分析方法和倒频谱预白化方法具有有效性和优越性。     

Research on Fault Evaluation of Armament Equipment Based on ADAMS

1 IntroductionNowadays the local wars suggest that the key of succedng is the comParison of intmptive force,though advanccd Weaponry is becOndng moe and moe impotant. As the convelltional opPrssiveweaPO, artillery still plays a necessary Psit in m(for war Howevec arhllery Inay encounter allkln(l8 of faultS in the course of maintenance alld suPpot of armament equipment fOr incorreetiyOperahng and other natural reasons, and the faults win direetly affect the wobong performace ofarhllery Rec…     

Application of Multi-sensor Information Fusion in the Fault Diagnosis of Hydraulic System

Aiming at the problem of incomplete information and uncertainties in the diagnosis of complex system by using single parameter,a new method of multi-sensor information fusion fault diagnosis based on BP neural network and D-S evidence theory is proposed. In order to simplify the structure of BP neural network,two parallel BP neural networks are used to diagnose the fault data at first; and then,using the evidence theory to fuse the local diagnostic results,the accurate inference of the inaccurate information is realized,and the accurate diagnosis result is obtained. The method is applied to the fault diagnosis of the hydraulic driven servo system( HDSS) in a certain type of rocket launcher,which realizes the fault location and diagnosis of the main components of the hydraulic driven servo system,and effectively improves the reliability of the system.     

An analysis of safety-critical digital systems for risk-informed design

This paper quantitatively presents the results of a case study which examines the fault tree analysis framework of the safety of digital systems. The case study is performed for the digital reactor protection system of nuclear power plants. The broader usage of digital equipment in nuclear power plants gives rise to the need for assessing safety and reliability because it plays an important role in proving the safety of a designed system in the nuclear industry. We quantitatively explain the relationship between the important characteristics of digital systems and the PSA result using mathematical expressions. We also demonstrate the effect of critical factors on the system safety by sensitivity study and the result which is quantified using the fault tree method shows that some factors remarkably affect the system safety. They are the common cause failure, the coverage of fault tolerant mechanisms and software failure probability.