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Design of a Tester for GOOSE Messages Performance Testing Defined in IEC 61850
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
Nowadays, electrical energy is a necessity and the use of intelligent power equipment is expanding. Of course, having a protocol for communicating between such equipment is not only useful but sometimes mandatory. In the past, each equipment manufacturer used its own method for communication, hence, the "IEC 61850" standard was proposed as a solution to solve the problem of communication between different equipment. In this research, we intend to design a tester to perform a performance test with for GOOSE messages. These messages are based on the IEC 61850 data set and have the ability to quickly and securely distribute input and output values at the system level, which are transmitted by a...
Circuit Printing for Low-Cost Electronics by Organic Inks
, M.Sc. Thesis Sharif University of Technology ; Sarvari, Reza (Supervisor)
Abstract
Due to the high cost of the conventional silicon-based circuits, printed electronic introduced as an ultra-low-cost saving techniques which are widely used in RFID tags, displays, sensors and thin film transistors and so on. Unlike the silicon-based devices, Organic materials are used in printed electronic devices, owing to this these devices can be used on large and flexible substrates like glass and plastic. Also in the printing method, there is no demand for expensive and time-consuming processes such as lithography or sputtering. Only by an ink-jet printer or graved cylinders the different layers of a device can be deposited. Besides these advantages of printed electronics to...
Rheological and sedimentation behaviour of nanosilver colloids for inkjet printing
, Article International Journal of Nanomanufacturing ; Volume 5, Issue 3-4 , 2010 , Pages 383-392 ; 17469392 (ISSN) ; Guenther, B. H ; Sharif University of Technology
2010
Abstract
Inkjet printing of colloidal metals is an attractive method for direct patterning of electrically conductive structures and interconnects in electronic devices, owing to low-cost, low-waste and simplicity of the process. In the present work, mixtures of well-dispersed silver nanoparticles and ethylene glycol were prepared for the inkjet printing process. Three different surfactants including PVP, MSA and AOT were added to study the stability of the nanosilver colloids. The effect of high-intensity ultrasonic treatment and temperature on the rheological properties was investigated utilising a rheometer in plate-plate geometry. It is shown that the viscosity of the ink increases with...
High-Performance fiber-shaped flexible asymmetric microsupercapacitor based on ni(oh)2 nanoparticles-decorated porous dendritic ni-cu film/cu wire and reduced graphene oxide/carbon fiber electrodes
, Article ACS Sustainable Chemistry and Engineering ; Volume 6, Issue 11 , 2018 , Pages 14574-14588 ; 21680485 (ISSN) ; Naderi, L ; Mohammadi, R ; Sharif University of Technology
American Chemical Society
2018
Abstract
Miniaturization of electronic devices with portable, flexible and wearable characteristics created a great demand for high-performance microscale energy storage devices with lightweight and flexible properties. Among the energy storage devices, wire-shaped supercapacitors (WSSCs) have recently received tremendous attention due to their tiny volume, wearability, high flexibility and potential applications in the next-generation portable/wearable electronic devices. Herein, we successfully fabricated a porous dendritic Ni-Cu film on Cu wire substrate (CWE) for fabrication of high-performance wire-type supercapacitors. The porous structure with dendritic morphology provides a high surface area,...
Effect of transverse and parallel magnetic fields on thermal and thermo-hydraulic performances of ferro-nanofluid flow in trapezoidal microchannel heat sink
, Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 31, Issue 7 , 2021 , Pages 2089-2111 ; 09615539 (ISSN) ; Khorasanizadeh, H ; Shafii, M. B ; Sharif University of Technology
Emerald Group Holdings Ltd
2021
Abstract
Purpose: This paper aims to study the thermal and thermo-hydraulic performances of ferro-nanofluid flow in a three-dimensional trapezoidal microchannel heat sink (TMCHS) under uniform heat flux and magnetic fields. Design/methodology/approach: To investigate the effect of direction of Lorentz force the magnetic field has been applied: transversely in the x direction (Case I);transversely in the y direction (Case II); and parallel in the z direction (Case III). The three-dimensional governing equations with the associated boundary conditions for ferro-nanofluid flow and heat transfer have been solved by using an element-based finite volume method. The coupled algorithm has been used to solve...
Iterative machine learning-aided framework bridges between fatigue and creep damages in solder interconnections
, Article IEEE Transactions on Components, Packaging and Manufacturing Technology ; 2021 ; 21563950 (ISSN) ; Fotuhi Firuzabad, M ; Samavatian, M ; Dehghanian, P ; Blaabjerg, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Costly and time-consuming approaches for solder joint lifetime estimation in electronic systems along with the limited availability and incoherency of data challenge the reliability considerations to be among the primary design criteria of electronic devices. In this paper, an iterative machine learning framework is designed to predict the useful lifetime of the solder joint using a set of self-healing data that reinforces the machine learning predictive model with thermal loading specifications, material properties, and geometry of the solder joint. The self-healing dataset is iteratively injected through a correlation-driven neural network to fulfill the data diversity. Outcomes show a...
Iterative machine learning-aided framework bridges between fatigue and creep damages in solder interconnections
, Article IEEE Transactions on Components, Packaging and Manufacturing Technology ; Volume 12, Issue 2 , 2022 , Pages 349-358 ; 21563950 (ISSN) ; Fotuhi Firuzabad, M ; Samavatian, M ; Dehghanian, P ; Blaabjerg, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Costly and time-consuming approaches for solder joint lifetime estimation in electronic systems along with the limited availability and incoherency of data challenge the reliability considerations to be among the primary design criteria of electronic devices. In this article, an iterative machine learning framework is designed to predict the useful lifetime of the solder joint using a set of self-healing data that reinforce the machine learning predictive model with thermal loading specifications, material properties, and geometry of the solder joint. The self-healing dataset is iteratively injected through a correlation-driven neural network (CDNN) to fulfill the data diversity. Outcomes...
Ceria reinforced nanocomposite solder foils fabricated by accumulative roll bonding process
, Article Journal of Materials Science: Materials in Electronics ; Volume 23, Issue 9 , September , 2012 , Pages 1698-1704 ; 09574522 (ISSN) ; Kokabi, A. H ; Miyashita, Y ; Mutoh, Y ; Rezayat, M ; Madaah Hosseini, H. R ; Sharif University of Technology
Springer
2012
Abstract
As one of the key technologies for high performance electronic devices, composite solders have been recently developed to improve thermal and mechanical properties of solder joints. In this study, accumulative roll bonding process was used as an effective alternative method for manufacturing high-strength, finely dispersed, void-free and highly uniform Sn-Ag-Cu/CeO 2 nanocomposite solders. Microstructural investigation of nanocomposite solders revealed that homogenous distribution of CeO 2 nanoparticle has been achieved and the eutectic as-cast morphology of the solder changed to recrystallized fine grained structure. As a result of severe plastic deformation during rolling, brittle and...
A novel soft-switching seven-level converter topology with self-voltage balancing ability
, Article IEEE AFRICON Conference, 23 September 2009 through 25 September 2009 ; 2009 ; 9781424439195 (ISBN) ; Poure, P ; Saadate, S ; Abbaspour Tehrani Fard, A ; Sharif University of Technology
Abstract
One of the major limitations of the multilevel converters is the voltage unbalance between different levels. The techniques to balance the voltage between the different levels normally involve voltage clamping or capacitor charge and discharge control. However, traditional Flying Capacitor Converter (FCC) may be quite limited by the voltage unbalance of flying-capacitors that is the most serious problem. This paper describes operating principles of a new softswitching seven-level converter topology based on FCC for self-voltage stabilization and balancing. By adding power electronic devices to the traditional FCC topology, the proposed topology regulates the DC bus voltage and balances the...
Model-based Reliability-Centered design of power electronics dominated microgrids
, Article 17th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2022, 12 June 2022 through 15 June 2022 ; 2022 ; 9781665412117 (ISBN) ; Blaabjerg, F ; Fotuhi Firuzabad, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
This paper proposes a model-based design approach for microgrids considering the aging of power electronic devices under different operating conditions. The proposed approach takes into account the physics of failure mechanisms in converter components as the failure prone devices in power systems. Furthermore, it considers the impacts of load profile on the aging of converter components and system performance. This approach facilitates accurate and optimized design of power electronic-based microgrids. According to this approach fragile links of power converters for a specified application can be identified. Moreover, the weakest converters based on their function in the microgrid can be...
A new scheme for the development of IMU-based activity recognition systems for telerehabilitation
, Article Medical Engineering and Physics ; Volume 108 , 2022 ; 13504533 (ISSN) ; Eslaminia, A. R ; Bakhshayesh, P. R ; Ejtehadi, M ; Alibiglou, L ; Behzadipour, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Wearable human activity recognition systems (HAR) using inertial measurement units (IMU) play a key role in the development of smart rehabilitation systems. Training of a HAR system with patient data is costly, time-consuming, and difficult for the patients. This study proposes a new scheme for the optimal design of HARs with minimal involvement of the patients. It uses healthy subject data for optimal design for a set of activities used in the rehabilitation of PD1 patients. It maintains its performance for individual PD subjects using a single session data collection and an adaptation procedure. In the optimal design, several classifiers (i.e. NM, k-NN, MLP with RBF as a hidden layer, and...
Fabrication of a 2.8 V high-performance aqueous flexible fiber-shaped asymmetric micro-supercapacitor based on MnO2/PEDOT:PSS-reduced graphene oxide nanocomposite grown on carbon fiber electrode
, Article Journal of Materials Chemistry A ; Volume 8, Issue 37 , 2020 , Pages 19588-19602 ; Shahrokhian, S ; Soavi, F ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Flexible and lightweight fiber-shaped micro-supercapacitors have attracted tremendous attention as next-generation portable electronic devices, due to their high flexibility, tiny volume, and wearability. Herein, we successfully fabricated a ternary binder-free nanocomposite of MnO2/PEDOT:PSS-rGO on a carbon fiber substrate for application in high performance fiber-shaped micro-supercapacitors. The synergistic effects of the different components in the fiber-shaped electrode help to deliver a high specific capacitance of 2.9 F cm-2 (194 F cm-3 and 550 mF cm-1) at a current density of 5 mA cm-2 and a long cycle life with 95% capacitance retention after 5000 cycles in 1 M Na2SO4 electrolyte. A...
A new delay attack detection algorithm for PTP network in power substation
, Article International Journal of Electrical Power and Energy Systems ; Volume 133 , 2021 ; 01420615 (ISSN) ; Jahangir, A. H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Time synchronization is one of the main issues for guaranteeing the correctness of actions depending on the time of measured data or detected events by electronic devices across industrial networks. According to the accuracy needed in different applications and networks, several synchronization protocols or algorithms have been proposed so far. The Precision Time Protocol, PTP, is one of the most accurate synchronization protocols introduced for automation applications. It has also been used in power grids and digital substations. However, due to the variety of cyber-attacks in electrical power systems in recent years, its security should be considered and evaluated as other substation...
Modeling the detection efficiency in photodetectors with temperature-dependent mobility and carrier lifetime
, Article Superlattices and Microstructures ; Volume 122 , 2018 , Pages 557-562 ; 07496036 (ISSN) ; Ahmadpour, M ; Mosavi, A ; Alharbi, N ; Gorji, N. E ; Sharif University of Technology
Abstract
We proposed a modeling procedure to calculate the impact of temperature on the detection efficiency in photodetectors based on CdTe materials. Temperature increase impacts on the electrical properties of the materials such as carrier mobility and carrier recombination lifetime. This impact which can be effective in some cases has been normally ignored in the modeling approaches presented in the literature. Here we show that increasing the temperature from 190 K to 300 K not reduces the mobility of both electrons and holes but also significantly reduces the carrier lifetime. The result will impact on electric-field within the depletion width of the device, drift and diffusion lengths which...
Influence of joint arrangement on the fracture behavior of lead-free solder joints
, Article Journal of Electronic Materials ; Volume 50, Issue 4 , 2021 , Pages 2117-2128 ; 03615235 (ISSN) ; Nourani, A ; Honarmand, M ; Assempour, A ; Sharif University of Technology
Springer
2021
Abstract
The capability to standardize the fracture strength of solder joints is an effective tool to investigate the reliability of electronic devices. To achieve this purpose, in this research, the influences of joint arrangement (loading arm and load sharing) on the level of constraint imposed on joint deformation, fracture energy, and generally, fracture behavior of solder joints were investigated. Fracture behavior of solder joints using double-cantilever-beam (DCB) specimens as a function of loading arm and load sharing (i.e., the distance between two solder joints) was studied under mode I loading conditions at a strain rate of 0.03 s−1. By increasing the loading arm, the fracture force, Fci,...
Continuous-time/discrete-time (CT/DT) cascaded sigma-delta modulator for high resolution and wideband applications
, Article WMED 2010 - 8th IEEE Workshop on Microelectronics and Electron Devices, 16 April 2010 through 16 April 2010 ; April , 2010 , Pages 33-36 ; 9781424465750 (ISBN) ; Sadeghi, K. H ; Ay, S. U ; Sharif University of Technology
2010
Abstract
This paper reports transistor-level design of a new continuous-time (CT), discrete-time (DT) cascaded sigma delta modulator (SDM). The combination of a CT first stage and a DT second stage was utilized to realize a high speed, high resolution analog-to-digital converter (ADC). Power consumption of CT first stage is lowered by optimizing the gain coefficients of CT integrators in a feedforward topology. Moreover double sampling (CDS) was used in second stage integrators to further reduce power consumption. Proposed new SDM is simulated in 0.18μm CMOS technology and achieves 84dB dynamic range for a 10MHz signal bandwidth. Total analog power dissipation measured was 44mW
Programming of memristor crossbars by using genetic algorithm
, Article Procedia Computer Science, 6 October 2010 through 10 October 2010 ; Volume 3 , October , 2011 , Pages 232-237 ; 18770509 (ISSN) ; Shouraki, S. B ; Sharif University of Technology
2011
Abstract
Recently announcement of a physical realization of a fundamental circuit element called memristor by researchers at Hewlett Packard (HP) attracted so much interests and opened a new field in configurable or programmable electronic systems because it has properties of the perfect switch. Combination of this newly found circuit element with nanowire crossbar interconnect technology, creates a powerful platform which is called memristor crossbar. It has been demonstrated that this structure can offer the potential of creating configurable electronic devices which can have applications in signal processing and artificial intelligence. In this paper, we will highlight the rule that Genetic...
Reliability assessment of some high side MOSFET drivers for buck converter
, Article 2013 3rd International Conference on Electric Power and Energy Conversion Systems, EPECS 2013, Istanbul ; 2013 ; 9781479906888 (ISBN) ; Kaboli, S ; Sharif University of Technology
2013
Abstract
Nowadays power electronic devices have a wide usage in the industries and different electrical equipment for power conditioning. As a point of view, reliability is one of important figure of merits that should be considered to have long life time and also have more probability to do exactly the proposed mission. In this paper some methods are presented to improve the reliability of power electronic components. Also some methods of system reliability improvement are reviewed. One group of converters is DC-DC step down converter which is used in different applications such as battery charger and voltage regulator. In this paper as an example, reliability of a DC-DC step down converter with...
Residual flux mitigation of protective current transformers used in an autoreclosing scheme
, Article IEEE Transactions on Power Delivery ; Volume 31, Issue 4 , 2016 , Pages 1636-1644 ; 08858977 (ISSN) ; Salehizadeh, M ; Vakilian, M ; Sanaye Pasand, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
To avoid saturation of a protective current transformer (CT) operating under an autoreclosing scheme, the CT size should be chosen much higher than a similar CT operating under a single-step fault clearing scheme. The main reason for this significant difference is that the residual flux (caused by the first stage of the fault) cannot be noticeably reduced during the deadtime interval of the reclosing process and, therefore, the occurrence of a subsequent fault can extremely saturate the CT. In this paper, a low-cost, low-power electronic device is developed and introduced to demagnetize the CT under the reclosing deadtime interval. It will be shown that by using this device, the required...
Current-Transformer saturation prevention using a controlled voltage-source compensator
, Article IEEE Transactions on Power Delivery ; Volume 32, Issue 2 , 2017 , Pages 1039-1048 ; 08858977 (ISSN) ; Vakilian, M ; Sanaye Pasand, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Current-transformer (CT) saturation causes severe distortion in the measured current waveform which may lead to maloperation of the protective devices. This paper proposes a low-cost, power-electronic device to prevent the CT from saturation. The proposed compensator is inserted in series with the relay in the CT secondary circuit and acts as a controlled voltage source (CVS). The proposed CVS generates a time-varying voltage to cancel the voltage developed across the CT burden; therefore, the CT magnetic flux remains almost constant and undistorted during the power system transients. It will be shown that this device can precisely compensate fault current, inrush current, and other probable...