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fault-diagnosis
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Review of Network Reduction Techniques and Their Applications in Transmission Network Fault Diagnosis
, M.Sc. Thesis Sharif University of Technology ; Bozorgmehry Boozarjomehry, Ramin (Supervisor)
Abstract
Monitoring and control of gas transmission networks are very challenging and important, this is due to the fact that interactions between various elements in the transmission network severely affect network’s overall performance. This makes it crucial for the monitoring and control systems to take into account the topology of the network, in their decision making and control scenario’s. On the other hand, in the event of any abnormality in the network behavior, , in order to accurately and quickly detect the cause of the abnormal conditions, there is a need for rapid and effective analysis of the network based on the measurements made therein and to identify the key and effective situations...
Development of an Intelligent Fault Diagnosing System for Diagnosis of Multiple Concurrent Asynchronous Faults for Tennessee Eastman Process
, M.Sc. Thesis Sharif University of Technology ; Bozorgmehry Boozarjomehry, Ramin (Supervisor)
Abstract
Fault diagnosis in complex processes is very difficult due to their complexity and dimensionality, so it is of great importance. In previous works, concurrent fault diagnosing methods have not been able to diagnose faults with overlapping symptoms. On the other hand, there is no established and general method by which asynchronous concurrent faults with overlapping symptoms can be diagnosed. The purpose of this work is to come up with such a method in order to mitigate the shortcomings of the available methods which are not appropriate to be used for such a problem. In this problem, the main objective is to come up with course of events of faults according to their times occurrence. The...
Fault Detection in Plant Wide
,
Ph.D. Dissertation
Sharif University of Technology
;
Bozorgmehry, Ramin
(Supervisor)
;
Shahrokhi, Mohammad
(Supervisor)
Abstract
The accurate fault diagnosing system design helps the process safety and also helps increasing the products quality of the process. In this project, the fuzzy system and neural network have been used for fault detection and diagnosis of a yeast fermentation bioreactor. In one case, parameters of membership functions are selected in a conventional manner. In second case, the optimal values of these parameters have been obtained using the genetic algorithm. In another case, the neural network system is used for fault detection. These three cases are compared based on their performances in fault diagnosis of a yeast fermentation bioreactor for three different conditions. The results indicate...
Design of a fault Tolerated Intelligent Control System for a Nuclear Reactor Power Control
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Naser (Supervisor) ; Salarieh, Hassan (Supervisor)
Abstract
Many advanced process plants and machines are extremely complex, and always depend on automatic control for satisfactory operation. In order to achieve and maintain system stability and assure satisfactory and safe operation, there is increasing demand for dynamic systems to continue acceptable operation following failures. Therefore failures detection has always been an important aspect of fault tolerant control design. In nuclear power plant, for example, tens of alarms can occur in a few second after a fault. Fault detection might be of utmost importance due to safety, political and other reasons. There are many methods to detect fault on the system. In this project approach based on...
On-line fault detection and isolation (FDI) for the exhaust path of a turbocharged SI engine
, Article ASME 2013 Dynamic Systems and Control Conference, DSCC 2013 ; Vol. 1 , 2013 ; ISBN: 9780791856123 ; Shahbakhti M ; Alasty, A ; Vossoughi, G ; Sharif University of Technology
Abstract
Detection and isolation of faults in the exhaust gas path of a turbocharged spark ignition (SI) engine is an essential part of the engine control unit (ECU) strategies to minimize exhaust emission and ensure safe operation of a turbocharger. This paper proposes a novel physics-based strategy to detect and isolate an exhaust manifold leakage and a closed-stuck wastegate fault. The strategy is based on a globally optimal parameter estimation algorithm which detects an effective hole area in the exhaust manifold. The estimation algorithm requires prediction of the exhaust manifold's input and output flows. The input flow is predicted by a nonlinear Luenberger observer which is analytically...
Reliable concurrent error detection architectures for extended euclidean-based division over (2m)
, Article IEEE Transactions on Very Large Scale Integration (VLSI) Systems ; Vol. 22, Issue. 5 , 2014 , pp. 995-1003 ; Azarderakhsh, R ; Lee, C. Y ; Bayat-Sarmadi, S ; Sharif University of Technology
Abstract
The extended Euclidean algorithm (EEA) is an important scheme for performing the division operation in finite fields. Many sensitive and security-constrained applications such as those using the elliptic curve cryptography for establishing key agreement schemes, augmented encryption approaches, and digital signature algorithms utilize this operation in their structures. Although much study is performed to realize the EEA in hardware efficiently, research on its reliable implementations needs to be done to achieve fault-immune reliable structures. In this regard, this paper presents a new concurrent error detection (CED) scheme to provide reliability for the aforementioned sensitive and...
Application of synchronised phasor measurements to wide-area fault diagnosis and location
, Article IET Generation, Transmission and Distribution ; Vol. 8, issue. 4 , 2014 , pp. 716-729 ; ISSN: 17518687 ; Ranjbar, A. M ; Sharif University of Technology
Abstract
This study introduces a novel approach to power system fault diagnosis by synchronised phasor measurements. Conventionally, faults are diagnosed through the status of protective relays and circuit breakers which are activated following a fault. However, the hidden failures of the protection system has itself often been among the main suspects of partial or widespread blackouts. This study proposes an alternative fault diagnosis approach independent of the function of the protection system. An analytical method is introduced for power system fault diagnosis using dispersed synchronised measurements and bus impedance matrix (Zbus). Fault inception is first detected by local phasor measurement...
On-line fault detection and isolation (FDI) for the exhaust path of a turbocharged SI engine
, Article ASME 2013 Dynamic Systems and Control Conference, DSCC 2013 ; Volume 1 , 2013 ; 9780791856123 (ISBN) ; Shahbakhti, M ; Alasty, A ; Vossoughi, G ; Sharif University of Technology
2013
Abstract
Detection and isolation of faults in the exhaust gas path of a turbocharged spark ignition (SI) engine is an essential part of the engine control unit (ECU) strategies to minimize exhaust emission and ensure safe operation of a turbocharger. This paper proposes a novel physics-based strategy to detect and isolate an exhaust manifold leakage and a closed-stuck wastegate fault. The strategy is based on a globally optimal parameter estimation algorithm which detects an effective hole area in the exhaust manifold. The estimation algorithm requires prediction of the exhaust manifold's input and output flows. The input flow is predicted by a nonlinear Luenberger observer which is analytically...
A circuit approach to fault diagnosis in power systems by wide area measurement system
, Article International Transactions on Electrical Energy Systems ; Volume 23, Issue 8 , 2013 , Pages 1272-1288 ; 20507038 (ISSN) ; Ranjbar, A. M ; Sharif University of Technology
2013
Abstract
Fault diagnosis following a disturbance in a power system is of great importance for the operators in the control center as a prerequisite for system restoration. In this article, for the first time, an analytic method for fault diagnosis, using the wide area measurement system (WAMS) and employing circuit rules, is developed. Instead of conventional information about status of protective relays and circuit breakers, voltage and current phasors at different points of the power network after fault occurrence are utilized. Because most of the power systems will be equipped with WAMS consisting of high-speed sampling features, the proposed method introduces a new application of WAMS for fault...
Rolling bearing fault detection by short-time statistical features
, Article Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering ; Volume 226, Issue 3 , 2012 , Pages 229-237 ; 09544089 (ISSN) ; Bastami, A. R ; Mba, D ; Sharif University of Technology
SAGE
2012
Abstract
Rolling element bearing fault diagnosis is a very important part of condition-based maintenance. In this article, a new method for detection of rolling element bearing defects is proposed. The method is based on the concept of the cyclostationarity of the vibration signal to find periodicity in statistical features of the vibration signal. Various statistical features are examined to find the best choice. Several case studies including inner race, outer race, and rolling element defects are investigated in this article. Comparison with the envelope analysis showed that the proposed method benefits from clearer defect frequency identification
High-Performance Fault Diagnosis Schemes for Efficient Hash Algorithm BLAKE
, Article 10th IEEE Latin American Symposium on Circuits and Systems, LASCAS 2019, 24 February 2019 through 27 February 2019 ; 2019 , Pages 201-204 ; 9781728104522 (ISBN) ; Bayat Sarmadi, S ; Ackie, A. B ; Azarderakhsh, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Augmenting the security of cryptographic algorithms by protecting them against side-channel active attacks (and natural faults) is essential in cryptographic engineering. BLAKE algorithm is an efficient hash function which has been developed based on Bernstein's ChaCha stream cipher. Because of the fact that Google has chosen ChaCha along with Bernstein's Poly1305 message authentication code as a replacement for RC4 in TLS for Internet security, BLAKE's implementation is of paramount importance. In this paper, we present high-performance fault detection schemes for BLAKE. Specifically, for the round function, two fault diagnosis approaches are developed and analyzed in terms of error...
Online static/dynamic eccentricity fault diagnosis in inverter-driven electrical machines using resolver signals
, Article IEEE Transactions on Energy Conversion ; Volume 35, Issue 4 , May , 2020 , Pages 1973-1980 ; Nasiri Gheidari, Z ; Tootoonchian, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Inverter driven electrical machines need resolver for position estimation and efficient electronic commutations. In this paper, the resolver signals are also used for the purpose of mechanical fault diagnosis. Therefore, a comprehensive procedure based on winding function (WF) method is presented to propose a noninvasive index to identify the mechanical fault's type (static/dynamic eccentricity) and even its percentage. In this regard, once the resolver signals are measured and saved in health condition. Then, during the operation of the motor, calculating the proposed index using the healthy and faulty signals leads to predict the fault type and its percentage. The success of the proposed...
Experimental study of rolling element bearing failure pattern based on vibration growth process
, Article Proceedings of the 29th European Safety and Reliability Conference, ESREL 2019, 22 September 2019 through 26 September 2019 ; 2020 , Pages 1179-1186 ; Behzad, M ; Ghodrati, B ; Taghizadeh Vahed, A ; Sharif University of Technology
Research Publishing Services
2020
Abstract
Rolling-element bearing (REB) Failure is one of the most common failure in rotary machines in industry. Therefore, this concern draws attention to the concept of diagnostic and the prediction of REB failure. The efficacy of vibration analysis in this area has led many researchers to focus on this topic in recent decades. Defective bearings such as fatigue, surface roughness, and corrosion can lead to disastrous accidents. Therefore, providing an algorithm for the detection and classification of bearing defects is valuable and useful. The prediction of the bearing's lifetime is important to ensure the planned production in an industrial unit. In this paper, different models for performance...
Model-Based Fault Diagnosis of the Gas Exchange System in a Turbocharged Gasoline Engine
, Ph.D. Dissertation Sharif University of Technology ; Alasty, Aria (Supervisor) ; Vossoughi, Gholamreza (Supervisor)
Abstract
Proper operation of a spark ignition engine is required by comfort demands of a vehicle driver and governmental legislations. Therefore it is essential to monitor, within an online technique, the engine and detect any fault which disrupts its operation. The gas exchange path (including the intake and exhaust subsystems) is an important part of turbocharged engines responsible for accurate control of both engine power and emissions. Monitoring the path for fault detection and isolation (FDI) has been always demanded due to many failures it may face since the turbocharger exasperates the harsh working conditions for components involved in the path. This paper presents a novel model-based...
Fault-Tolerant Operation of Three-Phase Dual Active Bridge Converter Against Semiconductor Power Switches Fault
, M.Sc. Thesis Sharif University of Technology ; Zolghadri, Mohammad Reza (Supervisor)
Abstract
The three-phase Dual Active Bridge DC-DC converter, by virtue of its various advantages, has been widely used in numerous industrial and sensitive applications. However, this converter includes a large number of power switching devices, which are the most fragile components in Power Electronics, and therefore, can pose a threat to appropriateness of the converter for such applications. Accordingly, introducing a fault-tolerant scheme for this converter is necessary, in order to meet the demands of high reliability and service continuity in aforementioned applications. In this thesis, firstly, the converter is studied during normal operation as well as under switch open-circuit fault, and the...
Develop a Monitoring Center Conceptual Framework for Chain Stores
, M.Sc. Thesis Sharif University of Technology ; Rajabi Ghahnaviyeh, Abbas (Supervisor)
Abstract
Among the equipment used in supermarkets, refrigeration systems should be the focus of energy efficiency initiatives; Because they are the biggest consumers of energy and refrigerant with significant maintenance costs. Fault detection and diagnosis (FDD) can provide considerable potential for energy savings as well as reduced maintenance costs. Although there have been numerous investigations of FDD for HVAC systems, there has been very little research on the application of FDD for supermarket refrigeration systems. Therefore, this thesis focuses on the application of FDD to these systems and helps to fill these research gaps. The studied system is a commercial refrigerator system on a...
Open-and short-circuit switch fault diagnosis for nonisolated DC-DC converters using field programmable gate array
, Article IEEE Transactions on Industrial Electronics ; Volume 60, Issue 9 , October , 2013 , Pages 4136-4146 ; 02780046 (ISSN) ; Jamshidpour, E ; Poure, P ; Saadate, S ; Zolghadri, M. R ; Sharif University of Technology
2013
Abstract
Fault detection (FD) in power electronic converters is necessary in embedded and safety critical applications to prevent further damage. Fast FD is a mandatory step in order to make a suitable response to a fault in one of the semiconductor devices. The aim of this study is to present a fast yet robust method for fault diagnosis in nonisolated dc-dc converters. FD is based on time and current criteria which observe the slope of the inductor current over the time. It is realized by using a hybrid structure via coordinated operation of two FD subsystems that work in parallel. No additional sensors, which increase system cost and reduce reliability, are required for this detection method. For...
An appropriate procedure for detection of journal-bearing fault using power spectral density, K-nearest neighbor and support vector machine
, Article International Journal on Smart Sensing and Intelligent Systems ; Volume 5, Issue 3 , 2012 , Pages 685-700 ; 11785608 (ISSN) ; Ahmadi, H ; Tabatabaeefar, A ; Sakhaei, B ; Sharif University of Technology
2012
Abstract
Journal-bearings play a significant role in industrial applications and the necessity of condition monitoring with nondestructive tests is increasing. This paper deals a proper fault detection technique based on power spectral density (PSD) of vibration signals in combination with K-Nearest Neighbor and Support Vector Machine (SVM). The frequency domain vibration signals of an internal combustion engine with three journal-bearing conditions were gained, corresponding to, (i) normal, (ii) corrosion and (iii) excessive wear. The features of the PSD values of vibration signals were extracted using statistical and vibration parameters. The extracted features were used as inputs to the KNN and...
Fault diagnosis within multistage machining processes using linear discriminant analysis: a case study in automotive industry
, Article Quality Technology and Quantitative Management ; Volume 14, Issue 2 , 2017 , Pages 129-141 ; 16843703 (ISSN) ; Baradaran Kazemzadeh, R ; Akhavan Niaki, S. T ; Sharif University of Technology
Taylor and Francis Ltd
2017
Abstract
Statistical process control provides useful tools to improve the quality of multistage machining processes, specifically in continuous manufacturing lines, where product characteristics are measured at the final station. In order to reduce process errors, variation source identification has been widely applied in machining processes. Although statistical estimation and pattern matching-based methods have been utilized to monitor and diagnose machining processes, most of these methods focus on stage-by-stage inspection using complex models and patterns. However, because of the existence of high rate alarms and the complexity of the machining processes, a surrogate modelling is needed to solve...
Quick diagnosis of short circuit faults in cascaded H-bridge multilevel inverters using FPGA
, Article Journal of Power Electronics ; Volume 17, Issue 1 , 2017 , Pages 56-66 ; 15982092 (ISSN) ; Zolghadri, M. R ; Rodriguez, J ; Shahbazi, M ; Oraee, H ; Lezana, P ; Schmeisser, A. U ; Sharif University of Technology
Korean Institute of Power Electronics
2017
Abstract
Fast and accurate fault detection is the primary step and one of the most important tasks in fault tolerant converters. In this paper, a fast and simple method is proposed to detect and diagnosis the faulty cell in a cascaded H-bridge multilevel inverter under a short circuit fault. In this method, the reference voltage is calculated using switching control pulses and DC-Link voltages. The comparison result of the output voltage and the reference voltage is used in conjunction with active cell pulses to detect the faulty cell. To achieve this goal, the cell which is active when the Fault signal turns to “0” is detected as the faulty cell. Furthermore, consideration of generating the active...