scholarly journals Methods of Fault Diagnosis in Fiber Optic Current Transducer Based on Allan Variance

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Lihui Wang ◽  
Gang Chen ◽  
Jianfei Ji ◽  
Jian Sun ◽  
Jiabin Qian ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Fiber Optic ◽  
High Reliability ◽  
Measurement Data ◽  
Allan Variance ◽  
Diagnostic Methods ◽  
Statistical Characteristics ◽  
Health State ◽  
Analysis Model ◽  
Calculation Results

To ensure low failure and high reliability of fiber optic current transducers (FOCTs), it is urgent to study methods of condition monitoring and fault diagnosis in FOCT. Faults in FOCT have statistical characteristics. With the analyzing of time domain and frequency domain features in fiber optic current transformers’ measurement data, we establish correspondence between the physical characteristics of key components in transformer and data features and then build diagnostic analysis model based on Allan variance. According to the Allan variance calculation results, we can diagnose fiber optic current transformer’s health state and realize faults location. Experiment results show that diagnostic methods based on Allan variance are accurate and effective to identify fault features.

Performance Model “Zooming” for In-Depth Component Fault Diagnosis

2010 ◽  
Author(s):  
N. Aretakis ◽  
I. Roumeliotis ◽  
K. Mathioudakis
Keyword(s):  
Fault Diagnosis ◽  
Measurement Data ◽  
Engine Performance ◽  
Main Tool ◽  
Performance Model ◽  
Diagnostic Methods ◽  
Performance Modelling ◽  
Engine Model ◽  
Path Component ◽  
Modelling Techniques

A method giving the possibility for a more detailed gas path component fault diagnosis, by exploiting the “zooming” feature of current performance modelling techniques, is presented. A diagnostic engine performance model is the main tool that points to the faulty engine component. A diagnostic component model is then used to identify the fault. The method is demonstrated on the case of compressor faults. A 1-D model based on the “stage stacking” approach is used to “zoom” into the compressors, supporting a 0-D engine model. A first level diagnosis determines the deviation of overall compressor performance parameters, while “zooming” calculations allow a localization of the faulty stages of a multistage compressor. The possibility to derive more detailed information with no additional measurement data is established, by incorporation of empirical knowledge on the type of faults that are usually encountered in practice. Although the approach is based on known individual diagnostic methods, it is demonstrated that the integrated formulation provides not only higher effectiveness but also additional fault identification capabilities.

Performance Model “Zooming” for In-Depth Component Fault Diagnosis

2010 ◽  
Vol 133 (3) ◽  
Author(s):  
N. Aretakis ◽  
I. Roumeliotis ◽  
K. Mathioudakis
Keyword(s):  
Fault Diagnosis ◽  
Measurement Data ◽  
Engine Performance ◽  
Main Tool ◽  
Performance Model ◽  
Diagnostic Methods ◽  
Engine Model ◽  
Path Component ◽  
1D Model ◽  
Compressor Performance

A method giving the possibility for a more detailed gas path component fault diagnosis by exploiting the “zooming” feature of current performance modeling techniques is presented. A diagnostic engine performance model is the main tool that points to the faulty engine component. A diagnostic component model is then used to identify the fault. The method is demonstrated on the case of compressor faults. A 1D model based on the “stage stacking” approach is used to “zoom” into the compressors, supporting a 0D engine model. A first level diagnosis determines the deviation of overall compressor performance parameters while zooming calculations allow a localization of the faulty stages of a multistage compressor. The possibility to derive more detailed information with no additional measurement data is established by the incorporation of empirical knowledge on the type of faults that are usually encountered in practice. Although the approach is based on known individual diagnostic methods, it is demonstrated that the integrated formulation provides not only higher effectiveness but also additional fault identification capabilities.

The Mechanical Mechanism Analysis for Mortar Arch Framework Slope Protection Structure

2013 ◽  
Vol 859 ◽  
pp. 143-148
Author(s):  
Yang Xu ◽  
Ding Ling Li ◽  
Li Peng ◽  
Yan Xiao ◽  
Yi Hua Nie
Keyword(s):  
Finite Element Analysis ◽  
Mechanism Analysis ◽  
Analysis Model ◽  
Element Analysis ◽  
Finite Element Analysis Model ◽  
Vertical Loading ◽  
Total Displacement ◽  
The Finite Element Analysis ◽  
Calculation Results ◽  
Real Scale

The finite element analysis model was built as the real scale for mortar arch framework slope protection, and the displacement and strain at different points were collected by vertical loading pressure. So the mechanical mechanism can be studied, and the analysis was done between calculation results and testing results of solid miniature model. The studying results show that the point on the arch foot is the worst stress place for each arch, and the total displacement increase nonlinear as the distance from the slope top increases, and the bump phenomenon exists in the bottom of slope, the points are likely to be broken.

Seismic Response Analysis of Soil-Structure Interaction on Base Isolation Structure

2013 ◽  
Vol 663 ◽  
pp. 87-91
Author(s):  
Ying Bo Pang
Keyword(s):  
Finite Element ◽  
Seismic Response ◽  
Soil Structure ◽  
Base Isolation ◽  
Soil Structure Interaction ◽  
Response Analysis ◽  
Analysis Model ◽  
Seismic Response Analysis ◽  
Structure Interaction ◽  
Calculation Results

As an effective way of passive damping, isolation technology has been widely used in all types of building structures. Currently, for its theoretical analysis, it usually follows the rigid foundation assumption and ignores soil-structure interaction, which results in calculation results distortion in conducting seismic response analysis. In this paper, three-dimensional finite element method is used to establish finite element analysis model of large chassis single-tower base isolation structure which considers and do not consider soil-structure interaction. The calculation results show that: after considering soil-structure interaction, the dynamic characteristics of the isolation structure, and seismic response are subject to varying degrees of impact.

Phenomenon of the Internet Immersion: Definition and Measurement

2021 ◽  
pp. 107-125
Author(s):  
L.A. Regush ◽  
◽  
A.V. Orlova ◽  
E.V. Alekseeva ◽  
O.R. Veretina ◽  
...  
Keyword(s):  
Convergent Validity ◽  
High Reliability ◽  
Diagnostic Methods ◽  
Internet Usage ◽  
Actual State ◽  
Time Range ◽  
The Internet ◽  
Digital Competence ◽  
Self Assessment ◽  
Internet Environment

The purpose of the study was to justify the essence of the “Internet immersion” phenomenon and to create a standardized method for its measurement. A comparative analysis of approaches to human behavior on the Internet environment and existing diagnostic methods has revealed a significant variety of categories and definitions used. At the same time, there is no definition that: first, characterizes the degree and quality of user's Internet activity; second, is free from negative and clinical connotations; and, third, describes a wider time range of Internet usage than the actual state of immersion. The authors substantiate the possibility of studying the phenomenon of the Internet immersion through the category of disposition. It consists of the readiness to use technical means and informational resources of the Internet to solve problems in various types of activities and communication. The authors identify traditional components in the structure of the Internet immersion phenomenon. These are, first of all, a cognitive component, represented by digital competence self-assessment; then, an affective component, represented by motivation and emotional and value-based attitude towards the Internet; and a behavioral component, represented by the amount of digital consumption. Based on this definition, it was possible to construct a compact 9-block “Index of the Internet immersion” questionnaire. Its standardization was conducted on the sample of 712 adolescents, aged from 11 to 17. Using the factor analysis, the structure of the questionnaire was identified. The first factor includes questions that relate to the time spent on the Internet and signs of dependence on it. The second factor includes questions that reveal the activity component and emotional attitude to the Internet. The third factor includes questions about experience and self-assessment of digital competence. The advantage of the “Index of the Internet immersion” questionnaire is a fairly high reliability for internal consistency of scales throughout the questionnaire. We also confirmed the sufficient convergent validity of the “Internet environment immersion Index” method with the “Scale of Problematic Internet Usage” by A.A. Gerasimova, A.B. Kholmogorova (adapted version of Generalized Problematic Internet Use Scale (GPIUS) by S. Caplan) and the Internet Addiction Test (IAT, K. Young), modified by V. A. Loskutova. This indicates its validity as an independent tool that does not duplicate other tools for semantically similar phenomena measurement. In the conditions of forced self-isolation that have developed in our country, the method of the Internet immersion diagnostics as an adequate and theoretically justified tool will allow us to study changes in the emotional state and behavior of teenagers on the Internet.

A Survey of New Technologies Used by Siemens Energy for the Monitoring and Diagnosis of a Global Fleet of Power Generation Systems

2009 ◽  
Author(s):  
Kurt Plotts ◽  
Evangelos Diatzikis
Keyword(s):  
Power Generation ◽  
New Technologies ◽  
Fiber Optic ◽  
Systems Design ◽  
Diagnostic Methods ◽  
Plant Performance ◽  
Blade Vibration ◽  
Engineering Knowledge ◽  
Design And Implementation ◽  
Power Generation Systems

Siemens has been on the cutting edge of the power generation business for over a century and has been providing diagnostics systems design and implementation since the early 1980s. Siemens Power Diagnostics® Services is designed to maximize plant performance, availability and profitability. Engineering knowledge, combined with the use of sophisticated tools, provides trending and analysis capabilities to address a broad range of operating needs specific to each customer. The goal of Power Diagnostics® is to enhance Siemens assistance to our customers through the detection of impending operational problems thereby helping to minimize unplanned outages and maximize power generation availability. A variety of new technologies are being harnessed to further this goal. A survey and discussion of these technologies will be the goal of this paper. Some of the projects discussed will be; Advances in the Power Plant Automated Diagnostics Systems, Blade Vibration Monitor (BVM), Fiber Optic Vibration Monitor (FOVM), and the Radio Frequency Monitor (RFM). The development and verification phases of research projects have often been conducted at customer sites. Many aspects of these technologies are new and will be of interest to gas turbine engineers as they are not widely applied yet. It is hoped that the reader will gain a new appreciation for the scope of modern diagnostic methods for power generation systems.

Fault Diagnosis of Space-borne Fiber Optic Gyros Based on Random Walk Coefficient Prediction and In-Orbit Calculation

2017 ◽  
pp. 1-1 ◽  
Author(s):  
Jing Jin ◽  
Ting Zhang ◽  
Kun Ma ◽  
Haoshi Zhang ◽  
Fei Teng ◽  
...  
Keyword(s):  
Random Walk ◽  
Fault Diagnosis ◽  
Fiber Optic

Multiple Fault Diagnosis Method in Multistation Assembly Processes Using Orthogonal Diagonalization Analysis

2008 ◽  
Vol 130 (1) ◽  
Author(s):  
Zhenyu Kong ◽  
Dariusz Ceglarek ◽  
Wenzhen Huang
Keyword(s):  
Fault Diagnosis ◽  
Product Information ◽  
Statistical Significance ◽  
Measurement Data ◽  
Space Representation ◽  
Assembly Process ◽  
Dimensional Control ◽  
Multiple Fault ◽  
Multiple Fault Diagnosis ◽  
Multistation Assembly

Dimensional control has a significant impact on overall product quality and performance of large and complex multistation assembly systems. To date, the identification of process-related faults that cause large variations of key product characteristics (KPCs) remains one of the most critical research topics in dimensional control. This paper proposes a new approach for multiple fault diagnosis in a multistation assembly process by integrating multivariate statistical analysis with engineering models. The proposed method is based on the following steps: (i) modeling of fault patterns obtained using state space representation of process and product information that explicitly represents the relationship between process-related error sources denoted by key control characteristics (KCCs) and KPCs, and (ii) orthogonal diagonalization of measurement data using principal component analysis (PCA) to project measurement data onto the axes of an affine space formed by the predetermined fault patterns. Orthogonal diagonalization allows estimating the statistical significance of the root cause of the identified fault. A case study of fault diagnosis for a multistation assembly process illustrates and validates the proposed methodology.

Sign in / Sign up

Export Citation Format

Share Document