基于定子电流Park矢量变换的感应电机故障诊断

通过提取定子电流信号Park矢量图作为电机故障特征，应用人工神经网络技术对故障特征进行分类与识别，从而避开复杂的谱分析技术，实验测试结果表明，该方法用于电机故障诊断可靠、有效，是一种实际可行的电机故障诊断方法。     

基于工业色谱仪的远程故障诊断系统的研究

简要介绍了工业色谱仪远程故障诊断结构框架；从网络框架的建立、动态网页对数据库的访问和故障数据库的设计等方面，研究了“基于Web的工业色谱仪的远程故障诊断系统”。讨论了Web服务器的构建；利用ASP语言编写动态、交互、高效的Web服务器应用程序；利用SQL实现故障数据库的建立以及对SQL数据库的安全管理，通过讨论和分析说明色谱仪远程故障诊断的设计思想可行性，有助于实现分析仪器的智能化诊断。     

Artificial neural network based fault identification scheme implementation for a three-phase induction motor

This paper presents results from the implementation and testing of a PC based monitoring and fault identification scheme for a three-phase induction motor using artificial neural networks (ANNs). To accomplish the task, a hardware system is designed and built to acquire three-phase voltages and currents from a 1/3 HP squirrel-cage, three-phase induction motor. A software program is written to read the voltages and currents, which are first used to train a feed-forward neural network structure using the JavaNNS program. The trained network is placed in a LabVIEW based program formula node that monitors the voltages and currents online and displays the fault conditions and turns the motor off. The complete system is successfully tested in real time by creating different faults on the motor.     

ActiveX控件在设备工况分析系统中的应用

以工况监视与分析诊断系统MFD系列为例 ,介绍了ActiveX控件在设备工况分析系统中的应用 ,阐述了信号分析控件中图形显示、控件事件响应、分析功能实现等问题的解决方法 ,并通过应用实例阐明了分析控件在系统模块化、可维护性、可升级性以及其在信号分析过程中所起的作用。     

Influence of faulting on a mine shaft—a case study: part II—Numerical modelling

The X41 shaft is the man and supply shaft at Copper Mine, Mount Isa, Australia. There has been observed evidence of degradation manifested by the development of cracks in the shaft concrete lining since the early nineties. In addition, the shaft steel structure is being deformed and needs regular and meticulous maintenance. The shaft degradation has been attributed to the presence of two major geological structures, the W41 and W42 faults, which intersect the shaft in two distinct locations.Since the X41 shaft gives a direct access to the Copper Mine, it has to remain operational for the mine life. An objective of this study was to gain a better understanding of the mechanisms inducing damage to the shaft. In order to assess the long-term integrity of the shaft, it was essential to evaluate the impact of its deformation, related to the late mining status of the Copper Mine and the presence of the two major faults. It was important to determine an estimate of the future rate of displacement, as well as the total displacement, for the rest of the mine life.This paper presents a case study whereby the causes of shaft degradation were examined. The influence of faulting and mining sequence on the stability of the main mine shaft were investigated by means of field investigations and numerical modelling. This paper concentrates on the numerical modelling performed as part II of this project. It presents exhaustively the methodology used to build the numerical model and presents the outcomes.     

An improved data fusion technique for faults diagnosis in rotating machines

The composite spectrum (CS) data fusion technique has been shown to simplify rotating machines faults diagnosis by earlier studies. Faults diagnosis with the earlier CS relied solely on the amplitudes of several harmonics of the machine speed, owing to the loss of phase information leading to its computation. The proposed improved CS applies the concept of cross power spectrum density for computing a poly-Coherent Composite Spectrum (pCCS) of a machine, which retains amplitude and phase information at all measurement locations. The present study compares the proposed pCCS method with the earlier CS method for faults diagnosis in rotating machines, using experimental data from a rotating rig. Results and observations show that the proposed pCCS offered a much better representation of the machines dynamics when compared to the earlier CS method and hence better fault diagnosis.     

Low cost monitoring system for safe production of hydrogen from bio-ethanol

In this paper a monitoring system is developed to guarantee safety operational conditions for the hydrogen production from bioethanol. The key idea is to detect the most critical faults with the minimum number of sensors. It can be done through a fault detectability index (FDI) which drives to the optimal measurements selection for building a proper monitoring system. The FDI calculation is based on principal component analysis (PCA) model with combined statistics. It takes into account those sensors already selected for control purposes and penalizes the use of new measurement devices. The overall methodology is tested for fifteen failures such as the catalyzer deterioration in the reforming reactor, faults at the fuel cell, sensors and actuators. Hence, the investment cost can be reduced drastically without losing quality of fault detection. The monitoring system with the selected sensors by the FDI performs better than using all the available plant measurements.     

白山水电站高压熔断器故障分析及处理

白山水电站常规和抽水蓄能机组电压互感器一次熔断器频繁发生爆断故障,严重影响了设备的安全运行,为查找高压熔断器爆断原因,分析了高压熔断器在制造、安装、运行、维护方面存在的问题,并提出了相应的处理措施。     

A novel multi-agent approach to identify faults in line connected three-phase induction motors

Three-phase induction motors (TIMs) are the key elements of electromechanical energy conversion in a variety of productive sectors. Identifying a defect in a running motor, before a failure occurs, can provide greater security in the decision-making processes for machine maintenance, reduced costs and increased machine operation availability. This paper proposes a new approach for identifying faults and improving performance in three-phase induction motors by means of a multi-agent system (MAS) with distinct behavior classifiers. The faults observed are related to faulty bearings, breakages in squirrel-cage rotor bars, and short-circuits between the coils of the stator winding. By analyzing the amplitudes of the current signals in the time domain, experimental results are obtained through the different methods of pattern classification under various sinusoidal power and mechanical load conditions for TIMs. The use of an MAS to classify induction motor faults allows the agents to work in conjunction in order to perform a specific set of tasks and achieve the goals. This technique proved its effectiveness in the evaluated situations with 1 and 2 hp motors, providing an alternative tool to traditional methods to identify bearing faults, broken rotor bars and stator short-circuit faults in TIMs.     

发电机定子绕组直流电阻超标故障分析

详细介绍了LY电厂#1发电机定子绕组故障情况，进行了原因分析．并提出了相应的反措。