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Class D power amplifier 2x 2 kW with switching power supply
Tylich, Ondřej ; Pazdera, Ivo (referee) ; Martiš, Jan (advisor)
The content of this thesis is a complete design of an amplifier working in class D, including a theoretical analysis. The thesis describes the functions of individual amplifier function blocks. The appropriate Class D amplifier topology is selected for the application. The design of the amplifier must correspond to the required power of 2x 2 kW to 4. The necessary calculations are performed to ensure the correct function of the amplifier. For reliability, it is necessary to select suitable terminal transistors. The thesis is a theoretical analysis of power supplies. Subsequently, a source with a suitable topology is designed, which will be designed to power the amplifier in class D. All necessary parameters are calculated, especially the power parts. The thesis deals with the design and complete implementation of the entire amplifier, starting with the design of the PCB and their production, subsequent installation, and recovery. After ensuring the function of all parts of the amplifier, various measurements are performed.
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DC-DC converter for onboard charging of electric vehicles
Holub, Miroslav ; Červinka, Dalibor (referee) ; Folprecht, Martin (advisor)
This master thesis deals with design of DC-DC converter for onboard charging of electric vehicle. Developed converter will mainly be used for charging stationary traction battery in laboratory. Output voltage of this charger will be adjustable by user in between 200 V and 450 V depending on the current charged battery configuration. Output current limit is set at 8 A. Since the converter will be supplied from standard household socket, the problem of power factor correction must be solved during the design. That is because a large part of this thesis is focused on describing the problematics of power factor correction. After that, active PFC module is designed, completed and performance of this module is verified. To achieve low overall losses and thus be able to keep small volume of the system, modern switching components based on Silicon Carbide were preferred. Beside laboratory use, completed system will be used to emphasize volumetric difference between onboard chargers based on old versus modern switching components.
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Electronic power-supply for high-pressure lamps
Prachař, Petr ; Kubíček, Michal (referee) ; Šotner, Roman (advisor)
This paper describes the principle functions of high pressure sodium and metal halide lamps. Electronic control circuit involves specific feaures (dimming effect). The proposal is implemented with emphasis on high efficiency and high power factor. An important factor in the proposal is also possibility to connect a many types of high-pressure discharge lamps with different electrical properties. The output inverter operates in resonant mode at high frequency and it is controlled by a microprocessor. It is powered by a bridgeless buck power factor correction.
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Electronic ballast for power LEDs
Vágner, Richard ; Martiš, Jan (referee) ; Červinka, Dalibor (advisor)
This diploma thesis deals with design of power LED driver. This driver contains electronic ballast circuits, converters, filters and control circuits. Overviews of circuits used in practice are listed along with analysis of power LED and considering options for selecting an appropriate design solution. Principles of creating the device, structure and problems of current source are described in thesis. Including detailed overview of converters, ballasts and topologies used in lighting systems with the selection of a suitable solution for the final device with an output power of 50 W. The thesis includes cooling dimensioning for selected power LEDs, input circuit with EMI filter, bridge rectifier, boost converter and flyback converter with pulse transformer.
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Effect of Interlayer Composition on Bond Strength between FRC Framework and Composite Veneer
Ibarra, Jonatanh José ; Pavelka,, Vladimír (referee) ; Poláček, Petr (advisor)
Hlavním cílem této práce je studium aktuálního problému adheze mezi kompozitními materiály, a určení vlivu složení mezivrstvy v pevnosti adhezivního spoje mezi vláknové (FRC) a částicové (PFC) kompozity, používané ve stomatologii. FRC tyčinky byly vytvořené na bázi komerční dimetakrylatové pryskyřice a skleněných S vláken. PFC byl vytvořen ze směsi pryskyřic (bis-GMA a PEGDMA), plněných drceným barnatým sklem. Celkově bylo připraveno a vyzkoušeno 84 vzorků. Vzorky byly rozdělené do pěti hlavních skupin. První skupina byla vytvořena ze série vzorků bez mezivrstvy. Zbylé čtyři skupiny byly rozděleny dle složení mezivrstvy (tloušťky a druhu pryskyřic). Částicové kompozity vzorků se lišily obsahem plniva (0, 10, 40 hm %). FRC tyčinky byly stejné pro všechny vzorky. Univerzální testovací přístroj ZWICK Z010 byl použit k zjištění smykové pevnosti adhezivního spoje všech vzorků. Rastrovací elektronový mikroskop byl použít k pozorování místa porušení. Ze získaných výsledků vyplívá, že s přidáváním mezivrstvy mezi vláknovým a částicovým narůstá smyková pevnost spoje. Důležitost těchto výsledků je způsobená tím, že v posledních letech použití těchto materiálů ve stomatologii narůstá a adheze zůstává jeden z hlavních problémů při klinické praxi.
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Functional model of a small hydro power plant control unit
Rusnák, František ; Arm, Jakub (referee) ; Benešl, Tomáš (advisor)
This semester work deals with realization of functional model of control unit for hydroelectric power station. Main task of this work is realization rectifier with active power factor correction, which is used instead of commonly used frequency converter. Control unit is designed for asynchronous motor in generator operation with self-excitation. The propeller turbine is used as propulsion. Theoretical part includes theory of the PFC converters. Practical part includes calculations for components of PFC converter and assembly of DPS PFC converter.
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Electronic ballast for sodium lamp
Eliáš, Jaroslav ; Vorel, Pavel (referee) ; Huták, Petr (advisor)
The aim is to get acquainted with the way the management and regulation of sodium lamps. This knowledge is then applied to design your own gear. The introductory section describes the basic characteristics of discharge light sources. Their behavior was verified by measuring and findings were used to create diagrams, mainly the control circuit. Theoretical design is developed by individual functional parts of the inverter.
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Resonant switched-mode power supply with PFC
Punar, Jan ; Drda, Václav (referee) ; Záplata, Filip (advisor)
This diploma thesis is focused on the LLC resonant power supply with power factor correction. The first part of the thesis is focused on a selection of a suitable controller for the control of this source. Here the emphasis is mainly on efficiency and EMC. The thesis also deals with the design of the scheme and the selection of suitable components. The thesis contains the design of the LLC power supply itself and also the power factor correction circuit - PFC.
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Power Factor Controllers for Switch-Mode Power Supllies
Gálus, Matej ; Steinbauer, Miloslav (referee) ; Murina, Milan (advisor)
The aim of this thesis is to design an active power factor correction (PFC) circuit for correcting a power factor of a switching power supplies. Various possible causes of bad AC mains power factor are discussed. Differences between linear and non-linear loads’ behaviour to AC mains are recognized and discussed. Various passive and active solutions for correcting current displacement and harmonic distortion are reviewed. Boost converter with quasi-resonant switching controlled by Texas Instruments’ UC3855 is chosen for highest total power factor for given power level against other topologies and its high efficiency and lower EMI against traditional boost converter. Various circuit parameters are simulated using PSpice. Complete circuit diagram for an 1kW output power level and worldwide mains voltage compatiblity is designed. After the device prototype was constructed, efficiency measurements were made and measured values are less than expected. This was apparently caused mainly due to absence of saturable reactor and implementation of resistive damping of the quasiresonant circuit’s parasitic resonance. Measured values of power factor are, however, very high and do meet the design expectations.
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