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    Feasibility Study and Conceptual Design of Solar Energy Source for Surface Train System

    , M.Sc. Thesis Sharif University of Technology Maleki, Sina (Author) ; Durali, Mohammad (Supervisor)
    Advancements in solar powered systems bring about the possibility for today’s transportation systems to be operated and driven by such a clean and renewable source of energy. The challenging point of this combination is to draw high power levels from such a low power density source of energy. As a result, employing an efficient power storage and management system becomes inventible. The subjects of this research are to design a grid connected system and evaluate its performance and feasibility in a real application (Tehran- Mehrshahr surface train – Tehran 5th Metro Line). The task includes sixteen pairs of DC transmission lines which are powered by CIGS solar module technology and four... 

    Standalone and Parallel Operation Optimization of Uninterruptible Power Supplies

    , Ph.D. Dissertation Sharif University of Technology Hasanzadeh, Amin (Author) ; Mokhtari, Hossein (Supervisor) ; Karimi, Masoud (Supervisor)
    Increase of sensitive customers to power quality has raised concerns in industries regarding requirements of quality power supply. Uninterruptible Power Supplies (UPSs) are known as efficient tools in providing reliable power supply to sensitive customer. However, in a UPS, getting a desired output requires appropriate structural implementation and successful output voltage control. On the other hand, due to the increase in sensitive loads in customers, the output power range of UPSs has increased. Consequently, design and producing high power UPSs is not economical. In addition, tendency to have high reliability power supplies disrespect of their physical locations has moved researcher... 

    Experimental evaluation of Master/Checker architecture using power supply- and software-based fault injection

    , Article Proceedings - 10th IEEE International On-Line Testing Symposium, IOLTS 2004, Madeira Island, 12 July 2004 through 14 July 2004 ; 2004 , Pages 239-244 ; 0769521800 (ISBN); 9780769521800 (ISBN) Rajabzadeh, A ; Miremadi, S. G ; Mohandespour, M ; Sharif University of Technology
    This paper presents an experimental evaluation of the effectiveness of the Master/Checker (M/C) architecture in a 32-bit Pentium® processor system using both power-supply disturbance (PSD) fault injection and software-implemented fault injection (SWIFI) methods. A total of 6000 faults were injected in the Master processor to measure the error detection coverage of the Checker processor. The results of the experiments with PSD fault injection show that the error detection coverage of the M/C architecture is about 66.13%, which is not quite effective. This low coverage depends on the high rate of Master processor hangs because of voltage fluctuation. The coverage increased to about 99.73% when... 

    Hardware Design for Cold Plasma Characterization Chamber

    , M.Sc. Thesis Sharif University of Technology Aghapour, Reza (Author) ; Rashidian, Bijan (Supervisor) ; Faez, Rahim (Supervisor)
    Cold plasma due to its special properties has many applications in the microelectronics industry. At the beginning of this study, a few examples of widely used plasmas and the requirements for driving their power sources have been investigated. To generate and characterize plasma, various topologies of DC power supply construction, including high-voltage low-current power supplies called multipliers and low-voltage high-voltage power supplies called converters, have been reviewed and compared.Circuit for pulse generating for plasma application has also been proposed and investigated. In the simulation section, after introducing, reviewing, and compareing the common types of simulators, the... 

    DSRD-based HVdc power supply

    , Article IEEE Transactions on Plasma Science ; Volume 46, Issue 6 , 2018 , Pages 2108-2113 ; 00933813 (ISSN) Samizadeh Nikoo, M ; Hashemi, M. A ; Vakilian, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    A novel high-voltage direct current (HVdc) power supply which has no transformer or voltage multiplier circuit is presented and analyzed in this paper. This is made possible upon the diodes storage delay phenomenon. This proposed power supply is compact, lightweight, and low cost. Its basic structure includes a diode with a proper reverse recovery specification that plays the role of a step-up transformer in the conventional HVdc supplies and a high-voltage capacitor which stabilizes the output voltage. This structure has remarkable advantages over the conventional transformer-based HVdc supplies, such as compactness, a low ripple output, and a low-cost power supply. Performance of the... 

    A reopened crowbar protection for increasing the resiliency of the vacuum tube high-voltage DC power supply against the vacuum Arc

    , Article IEEE Transactions on Plasma Science ; Volume 47, Issue 5 , 2019 , Pages 2717-2725 ; 00933813 (ISSN) Pouresmaeil, K ; Kaboli, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    High-voltage power supplies (HVPSs) are widely used to supply vacuum tubes. The amount of delivered energy from the HVPS to the tube is an important issue during the vacuum arc in the tube. The conventional protection mechanism consists of a shunt crowbar which diverts the fault current from the tube to itself as a parallel path. The crowbar circuit is usually built of the devices without the turn-off capability. It is a drawback since the output of the power supply is shortened for a long time. Thus, the restoration time of these power supplies is excessive. This demerit can have detrimental effects on mission-critical applications. In this paper, the insulated-gate bipolar transistor... 

    A robust short-circuit fault diagnosis for high voltage DC power supply based on multisensor data fusion

    , Article 10th International Power Electronics, Drive Systems and Technologies Conference, PEDSTC 2019, 12 February 2019 through 14 February 2019 ; 2019 , Pages 659-664 ; 9781538692547 (ISBN) Ayoubi, R ; Kaboli, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Short-circuit fault (SCF) detection is mandatory in a high voltage DC power supply (HVPS) to prevent fatal damage. The majority of converters employ a single sensor to detect the SCF. This attribute increases the interference vulnerability of the fault detection (FD) system in the presence of noise. Therefore, miss detections and false alarms are possible to occur. Miss detections and false alarms are harmful catastrophes in most applications. A commonly used method to suppress the noise impacts is using a low-bandwidth low-pass filter. However, the use of the low-bandwidth low-pass filter reduces the speed of FD due to the filter delay. This paper proposes a fast FD algorithm based on... 

    A Vacuum arc diagnosis method for the high voltage power supply of vacuum tubes

    , Article 2019 International Vacuum Electronics Conference, IVEC 2019, 28 April 2019 through 1 May 2019 ; 2019 ; 9781538675342 (ISBN) Ayoubi, R ; Rahmanian, M ; Kaboli, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Vacuum tubes are widely used for various applications. These vacuum tubes are supplied by high voltage power supplies. The amount of delivered energy from the high voltage power supply to the vacuum tube is an important issue during the vacuum arc in the tube. The protection mechanism consists of a shunt crowbar which diverts the fault current from the tube to itself as a parallel path. Detection of the vacuum arc is crucial and only one sensor is usually employed to detect the vacuum arc. This characteristic intensifies the interference susceptibility of the vacuum arc diagnosis system in a noisy environment. As a result of the noise, the arc detection system can report false alarms. False... 

    A comprehensive design of the thyristor-based crowbar for vacuum tube high-voltage dc power supplies

    , Article IEEE Transactions on Plasma Science ; Volume 48, Issue 6 , 2020 , Pages 2202-2209 Pouresmaeil, K ; Kaboli, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2020
    High-voltage power supplies (HVPSs) are widely used to drive vacuum tubes, inherently susceptible to vacuum arc faults. Owing to the considerable cost of vacuum tubes, the HVPS should enjoy a reliable, fast protection mechanism. A common protection mechanism against vacuum arc faults is the shunt crowbar. The crowbar diverts the energy stored in the elements of the HVPS through itself as a parallel path, thereby protecting vacuum tubes from irrecoverable damages. Among all types of the shunt crowbar, the thyristor-based crowbar along with the fault current limiter (FCL) resistors attracts more attention because of its more reliable operation. The absence of the comprehensive design procedure... 

    An advanced distributed power supply for power electronic transformers

    , Article IECON 2007, 33rd Annual Conference of the IEEE Industrial Electronics Society, Taipei, 5 November 2007 through 8 November 2007 ; 2007 , Pages 2038-2043 ; 1424407834 (ISBN); 9781424407835 (ISBN) Saghaleini, M ; Hekmati, A ; Farhangi, S ; Sharif University of Technology
    The idea of power electronic transformer (PET), which work with solid-state switches, have been considered noticeably recently. Every power electronic transformer has several parts which each of them needs its own reliable supply voltage. So the appropriate performance of a PET depends on the existence of various proper supply voltages. The distributed power supply (DPS), which can produce several different supply voltages simultaneously with various powers and high reliability, may be the optimum choice available for the supply of different modules of a PET. Additionally, distributed energy generation sources may be used as the alternative source for the PET which in that case it's... 

    nvestigating and Using of an Optimal Controller for Parallel 3-Phase UPS

    , M.Sc. Thesis Sharif University of Technology Nazaripouya, Hamid Reza (Author) ; Mokhtari, Hossein (Supervisor)
    In this thesis first of all the different approaches of control and parallel of multi-modular inverter system were investigated. These methods have been categorized and examined separately, and they were compared with each other in terms of quality and quantity. Afterwards, Active current sharing technique due to its high reliability was selected as the fundamental control approach. Among different ways for active current sharing, Avarage load sharing was chosen for its acceptable stability compared with other method. Approaching this goal, for the first time optimal control strategy and LQR method was proposed to parallel 3-phase inverters.At first, the problem was edited to be compatible... 

    Analysis of High Voltage Pulsed Power Supply Based on Parallel Modules via Pulse Transformer

    , M.Sc. Thesis Sharif University of Technology Hadizade, Amir Abbas (Author) ; Kaboli, Shahriyar (Supervisor)
    In this thesis, pulsed power structures containing a step up high voltage transformer with large transformer ratio are investigated. In pulsed power applications, a step up pulse transformer is a proper choice in the cases in which a low primary voltage is available. The noticeable advantage of employing these transformers is the ability to use several modules in the primary side of the transformer. However, it should be noticed that the primary side current of the transformer is large. So to solve this problem, the number of primary windings could be increased and the primary large current can be shared between these windings. In this thesis, the sharing methods are investigated and the... 

    Design and Implementation of a High-Efficient High-Power-Density Telecom Battery Charger using Planar Matrix Transformers

    , M.Sc. Thesis Sharif University of Technology Nazerian, Emad (Author) ; Tahami, Farzad (Supervisor)
    In creating a telecom battery charger there are three challenging factors which are high power density, high efficiency and modularity. A telecome battery charger consist of a rectifier with power factor correction capability and a DC-DC converter. The power stage of DC-DC converter with high output current and low output voltage has a vital role in the battery charger. The isolation transformer and magnetic component of LLC resonant tank are two huge and heavy parts of the DC-DC converter. With the emergence of GaN and SiC switches pushing frequency to to megahertz is possible which resulted in decreasing the volume of passive divices. But with increasing the frequency, designing of the... 

    Analysis of the Effect of High-Power Microwave Tube Internal Fault on High Voltage Power Supply and Protection System

    , M.Sc. Thesis Sharif University of Technology Atharijoo, Esmaeel (Author) ; Kaboli, Shahriyar (Supervisor)
    RF amplifier are one of the most important part of communication industry. microwave tubes are of the most sensitive and expensive parts of such systems, protection measures are of high importance. One of the phenomena that cause failure or degradation of tubes is electric arc in cathode of the tubes and dissipating energy due to that. In order to prevent the tubes from undergoing such harm, protection must be put into consideration. Furthermore, the limit of this dissipating energy determines the capacitor needed at the output of the power supply of the cathode. Since the value of the capacitor is directly proportionate to the amount of ripple of the output voltage, an exact calculation of... 

    Design and Construction of High-voltage Linear Regulator with Minimal Losses for Power Supply of Microwave Tube Cathode

    , M.Sc. Thesis Sharif University of Technology Osanloo, Mohsen (Author) ; Kaboli, Shahriyar (Supervisor)
    Microwave tubes are widely used in the telecommunications transmitters. high voltage power supplies are used to feed them. According to the specifications that arises for microwave tubes, To take advantage of these tubes need to maintain and stabilize voltage in a certain amount to be felt. If the tube supply voltage changes, the desired output parameters such as RF output power quality will change. To stabilize the voltage is within acceptable limits provided in different ways. One common method is the use of switching regulators due to the high efficiency compared to linear regulators considered. But it also will bring problems. Some of these problems can be pointed to electromagnetic... 

    Design and Implement of an Ultra Low Ripple Power Supply for Cathode of Microwave Tube

    , M.Sc. Thesis Sharif University of Technology Jalali, Saeed (Author) ; Kaboli, Shahryar (Supervisor)
    The purpose of this Thesis is designing and constructing of high voltage power supply with very low ripple. Proposed method of this thesis is formed of two sections. In this proposed structure, in first section, structure is on basis of diodes rectifier that has been used for producing main portion of output load energy. Second section uses with aim of regulating of first stage voltage. In attention to existence of noises and available offsets in different sections of proposed circuits, model is basis of two stages structure. Sampling of output voltage by using of resistance divider for main loop of circuit has been done. So noises and offsets available in circuit act as prevented factor... 

    Design and Fabrication of Variable DC Current Source for Microwave Tube Solenoid

    , M.Sc. Thesis Sharif University of Technology Hashemi, Hamidreza (Author) ; Kaboli, Shahriyar (Supervisor)
    In order to adjust the electrons beam in microwave lamps, an accurate electromagnetic field that is produced by a solenoid is required. The precision of the magnetic field generated by this solenoid is very important, and in advanced systems this precision is less than 10 ppm. This system is used to adjust the radiation rate for producing a variety of radiopharmaceutical. The major problem of the system is that the electron beam changes by time due to a change in the magnetic field, and this event causes the operator's room to be radiated. Constant calibration of this system is also very demanding and impractical. An example of these highly accurate (several ppm) systems are used in the... 

    Design and Implementation of a Regenerative Programmable Voltage Source

    , M.Sc. Thesis Sharif University of Technology Ghasemizadeh, Roozbeh (Author) ; Zolghadri, Mohammad Reza (Supervisor)
    Programmable AC Power Supply is a part of any Grid Simulator. Grid simulator is a system that, as a voltage source, can produce various power grid voltage waveforms in the output, and as a load, can draw different currents of ordinary loads from the power grid. The application of Grid Simulators is testing many grid connected systems, such as chargers, power supplies, PV inverters and etc. The purpose of this thesis is to design and build a 3 kW Programmable AC power supply, which can be used as a part of a grid simulator in future works. In this thesis, back to back converter topology is used for implementation of the programmable AC power supply. This back to back converter consists of an... 

    Control of Three-phase UPS with Nonlinear Load Using Disturbance Observer Considering Transformer Concerns

    , M.Sc. Thesis Sharif University of Technology Shahriari, Zohair (Author) ; Tahami, Farzad (Supervisor)
    Nowadays, non-linear loads comprise an important part of electrical grids. One of the most essential sources of nonlinear loads is switching power supplies, which mainly include power electronic rectifiers. When power outage occurs, Uninterruptible Power Supplies (UPS) must be able to supply these loads. The nonlinearity of the load has a significant effect on the Total Harmonic Distortion (THD) of the output voltage, which may not be easily reduced, especially in three-phase inverters. Furthermore, the presence of isolating transformers in these power supplies limits the control of harmonics and intensifies the nonlinear effects of the system.In this Master Thesis, a disturbance observer is... 

    A new self-powered electromagnetic damper for structural vibration control

    , Article Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2017, 26 March 2017 through 29 March 2017 ; Volume 10168 , 2017 ; 0277786X (ISSN); 9781510608214 (ISBN) Jamshidi, M ; Chang, C. C ; Fiberguide Industries; Frontiers Media; OZ Optics, Ltd.; Polytec, Inc.; The Society of Photo-Optical Instrumentation Engineers (SPIE) ; Sharif University of Technology
    SPIE  2017
    This paper presents a new self-powered hybrid electromagnetic damper that can mitigate vibration of a structure. The damper is able to switch between a power-regenerative passive mode and a semi-active mode depending on the power demand and capacity. The energy harvested in the passive mode due to suppression of vibration is employed to power up the sensing and electronic components necessary for the semi-active control. This provides a hybrid control capability that is autonomous in terms of its power requirement. The device mechanism and the circuitry that can realize this self-powered electromagnetic damper are described in this paper. The parameters that determine the device feasible...