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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Integrating Wind Power into The Electric Grid : Predictive Current Control Implementation

Badran, Ahmad January 2020 (has links)
The increasing penetration of wind power into the power system dominated by variable-speed wind turbines among the installed wind turbines will require further development of control methods. Power electronic converters are widely used to improve power quality in conjunction with the integration of variable speed wind turbines into the grid. In this thesis, a detailed model of the Predictive Current Control (PCC) method will be descripts for the purpose of control of the grid-connected converter. The injected active and reactive power to the grid will be controlled to track their reference value. The PCC model predicts the future grid current by using a discrete-time model of the system for all possible voltage vectors generated by the inverter. The voltage vector that minimizes the current error at the next sampling time will be selected and the corresponding switching state will be the optimal one. The PCC is implemented in Matlab/Simulink and simulation results are presented.
362

Provoz elektrizační soustavy s velkým počtem netočivých zdrojů elektrické energie / Power system operation with a large number of non-rotating power sources

Dohnal, Martin January 2017 (has links)
This diploma thesis deals with the simulation of various operating situations in the network with many non-rotating power sources, especially focusing on frequency stability. Non-rotating power source is any source that delivers its power to the grid via power electronics. The first part of the thesis describes power system of the Czech Republic and its future development. In the next section, there is short description of today's most common non-rotating power sources. The third part deals with power regulation of the frequency in the grid. The following part describes the models of electrical circuit created for use in PSCAD simulations. The penultimate part describes simulations performed on a model of the network with many non-rotating power sources, which also includes rotating sources. The last part describes simulations performed on a model of the network that is composed of non-rotating power sources only.
363

Návrh fotovoltaického systému rodinného domu / Design of photovoltaic system for a family house

Darebný, Tomáš January 2017 (has links)
Basic knowledge of photovoltaic energy transformation, devices and materials, used in photovoltaic are summarized in this master's thesis. The main goal of this thesis is orientation in the photovoltaic systems used these days and explain advantages and disadvantages of these systems during the design phase.
364

Návrh úprav letounu VUT 001 MARABU s pohonem vodíkovými palivovými články a bateriemi / Design of the Aircraft VUT 001 MARABU Modification Powered by Hydrogen Fuel Cells and Batteries

Bencalík, Karol January 2009 (has links)
The main topic of this thesis is a design of VUT 001 airplane fuel transformation by means of fuel cells and storage batteries. A list of components available on the market was drawn up, their building in the airplane and the engineering design for mounting the electric motor into the structure. The thesis also includes the mass and centering analysis of flight performance and stability control.
365

Třífázový střídač pro napájení vysokootáčkového asynchronního motor / Three-phase inverter for high-speed induction motor

Pinďák, Michal January 2018 (has links)
The goal of this master´s thesis is primarily the theoretical analysis of three-phase inverters and subsequent familiarization of the reader with their detailed practical structure. The first part is devoted to the general definition of the power semiconductor converter as such. The following part describes the principle of three-phase pulse width modulation including the widely used principle of scalar control of induction motors. The second half of the thesis is already focused on the practical design of a three-phase inverter for a 50 kW high-speed induction motor. This section explains the problem of sizing and selecting all of the sub-elements of the inverter based on the parameters specified by the end user of the device.
366

Testovací pracoviště pro hybridní a síťové střídače / PV inverter and hybrid inverter test bench

Sedlačko, Jozef January 2018 (has links)
Electricity production from photovoltaic power plants has been one of the fastest growing energy industries in the last decade. Number of small power inverters working parallelly with the low voltage grid is growing. At the same time, the requirements for the correct behaviour of network inverters in the network by the distribution grid operators are also increasing. The thesis deals with creation of a workplace for testing the operational and technical requirements for micro-sources. The first part of the thesis consists of literature search of inverter demands according to the current rules for parallel production operation. The second part deals with the setting up of test procedures and automation. The last part evaluates selected tests of the functions of the inverters.
367

Pojezdový mechanismus mostového jeřábu / The bridge crane's travel mechanism

Žid, Miroslav January 2018 (has links)
The aim of this master thesis is to design replacing the central drive of the overhead crane with dislocated drives. It´s a tong crane with the lifting capacity of 63 tons, located inside the hall. In the thesis is processed functional calculation of two types of drives, the associated types of brakes and the coupling element. Next there is a strength control of a new mechanism seat and a selected components. This whole leads to the output, which is the drawing documentation.
368

Testovací pracoviště pro hybridní a síťové střídače / PV inverter and hybrid inverter test bench

Sedlačko, Jozef January 2018 (has links)
Electricity production from photovoltaic power plants has been one of the fastest growing energy industries in the last decade. Number of small power inverters working parallelly with the low voltage grid is growing. At the same time, the requirements for the correct behaviour of network inverters in the network by the distribution grid operators are also increasing. The thesis deals with creation of a workplace for testing the operational and technical requirements for micro-sources. The first part of the thesis consists of literature search of inverter demands according to the current rules for parallel production operation. The second part deals with the setting up of test procedures and automation. The last part evaluates selected tests of the functions of the inverters.
369

Energetický model lineární osy s kuličkovým šroubem a servopohonem / Energetic model of linear axis with ball screw and servodrive

Sládek, Vojtěch January 2019 (has links)
The aim of the thesis was to study the Energy Models of Linear Axes with Ball Screws and Servo Drives, to analyze the individual parts of the axis with respect to losses, the methodology of calculating the losses on the electrical part and the mechanical part of the drive and creating a complex algorithm that calculates the energy consumed for the specified motion. The thesis is divided into a theoretical and practical part, where the theoretical part is divided into the treatise on the electrical part of the axis and its losses and the part that deals with the mechanical part and its losses. The calculation is divided into the basic verification algorithm and the calculation on the given example. Each calculation is calculated for both linear acceleration and S-curve acceleration. For both types of acceleration, the result of energy and its course over time is also the waveforms of position, velocity, acceleration, angular acceleration, moments, powers, power, speed and currents over time.
370

DC/DC měnič pro záložní zdroje / DC to DC inverter for backup power supplies

Eliáš, Marek January 2019 (has links)
This thesis deals with the design of a DC/DC converter designed for charging supercapacitors from the 36 V voltage source and consequent back transformation of supercapacitors voltage to the required output voltage. In the thesis the designs of decreasing and increasing DC/DC converters including schematics and calculations of individual components are presented and described. The calculations necessary for the supercapacitors to meet the 10Wh energy condition and the voltage balancer on the capacitors are given below. Completely designed equipment will be assembled and tested on supercapacitors with lower energy.

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