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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.
1

Non-Intrinsic Differential-Mode Noise in Switching Power Supplies and Its Implications to EMI Filter Design

Qu, Song 23 February 1999 (has links)
Electromagnetic Interference (EMI) problems in switching power supplies have been traditionally treated with cut-and-try approaches. In recent years, advancement has been made to better understand the problems and minimize the cut-and-try portion of the design process. However, there are still phenomena difficult to explain in many practical design situations. Often, the problems may be solved by luck but many puzzles remain unsolved. If not fully understood, these puzzles are very likely to come back to haunt the designers. According to the conventional theory, there are two modes of noise: the Differential-Mode (DM) noise and the Common-Mode (CM) noise. Recently, a new noise-coupling mode called Non-Intrinsic Differential-Mode (NIDM) noise was uncovered accidentally in the process of explaining certain EMI filter action [1]. This phenomenon has never been thoroughly studied. The focus of the present thesis is to investigate the NIDM phenomenon and its implications to practical EMI filter design issues. The generation mechanism and basic characteristics of this phenomenon will be briefly reviewed, which is crucial to the understanding of the remaining parts of the research. Two essential diagnostic tools are introduced. One is the DM/CM noise separator and the other is the zero-span mode operation of a spectrum analyzer. The results of the investigation will be presented. The results will be presented using practical examples, which tie the phenomenon to filter design issues. In some examples, explanations are given to dispel the puzzles commonly encountered in the practice. A filter design procedure is suggested for off-line power supplies. This procedure incorporates the NIDM phenomenon into an existing design procedure. Only first-order and second-order filter topologies are included in the discussion. / Master of Science
2

A study of the relationship between R&D-Marketing integration in the product innovation process and organizational performance for switching power supply firm.

Lee, Sheng-chien 28 July 2003 (has links)
Abstract This study is to investigate the status quo and relationship between R&D-Marketing integration in the product innovation process and organizational performance. Based on the company registered in 2003, a target population composed of 259 Switching Power Supply(SPS¡^companies is formed. Questionnaires were completed by managers responsible for marketing or R&D-Marketing departments. E-mail survey were employed to collect the data and use correlation analysis, one-way ANOVA and hierarchical regression analysis to analysis the data. It is found that the organizational factors variations exist in the integration of department and have positive influence on various activities when perpetual department was established and the manager is responsible for both marketing and R&D-Marketing department. Moreover, the result of research shows organizational factors have positive influence on department integration, and the mutual participation of members is most important. Besides, organizational factors will affect financial performance and program accomplish by integration of R&D-Marketing respectively of organizational category and chief factor. Based on the research findings, the perpetual department for developing new product and co-operated managers are suggested. In addition, mutual participation of members and establishing information network and database to reduce the gap of information between two departments deserve more attention so that the new product¡¦s performance could be improved. Keywords : switching power supply , new product development, department integration, organizational performance
3

Řízení svítidla LED / LED luminaire control

Jankovský, Martin January 2021 (has links)
The main topics of the thesis are luminaries based on LED technology and methods for driving them. The aim of theoretical part is to offer basic knowledge about LEDs, their categories, advantages and disadvantages. The basic methods for driving LED modules are also presented. Based on these facts the design of LED switching power supply for street lighting is presented. The aim is to reach high power factor. The function of the devices is presented by examining parts of the power supply.
4

Three Phase Switched Reluctance Motor Control Using A Flyback Resistor C Dump Converter Control

Huang, Yi-Wen 31 July 2005 (has links)
Switched Reluctance Machine (SRMs) are receiving significant attention for industries and homes in the last decade. Due to their rugged brushless design, high reliable and an outstanding performance over a wide speed range. The stator and rotor of an SRM have a double salient pole and the rotor has no windings and magnets, its torque generating is quite nonlinear and has high torque ripple. Therefore, sophisticated switching and control technologies are needed to improve its driving performance. The cost and performance of SRM drives are highly dependent on the converter topologies and motor structure, so that developments in the convert topologies have been made in parallel with motor design. The objective of this thesis is proposed three phase Switched Reluctance Machine using a fly back resistor C Dump Converter to replace the tradition Bridge Converter. It can reduce switching losses, to reduce converter production cost with a simpler circuit. At the end, a digital signal processor based control system is used to test the laboratory make drives .
5

Řiditelný spínaný zdroj 0-1000 V / 100 W / Controllable switching power supply 0-1000 V / 100 W

Hofmann, Oldřich January 2017 (has links)
The thesis deals with the design and construction of a switching power supply with output voltage adjustable from 0 to 1200 V and rated power of 120 W, which will be used to replace the existing high voltage power supply for the irreversible electroporation (IRE) device developed at UVEE FEEC BUT. The thesis focuses on a basic description of the IRE device, a description of usable converter topologies and a selection of the best topology for the required purpose. The selection of the control circuit concept and its design are also integral parts of the thesis. The final part of the thesis contains the assembly of the power supply and the measurement verifying its function.
6

Stejnosměrný výkonový zdroj / DC Power Supply

Kovář, Josef January 2017 (has links)
This master thesis concerns the design of DC power suply, which will be used for technological processes in engineering. This thesis concludes design of components and control curcuits for switching power supply. Output parameters of the machine will be measured.
7

Impulzní zdroj na rezonančním principu s kompenzací účiníku / Resonant switched-mode power supply with PFC

Punar, Jan January 2020 (has links)
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.
8

Zařízení pro Indukční ohřev pro účely uměleckého kovářství / Induction heating apparatus for artistic blacksmithing purposes

Šmarda, Vladislav January 2020 (has links)
This Diploma thesis deals with the design of induction heating inverter. The main subject is optimalization for blacksmiths. There is described the designing procedure for power components and also designing of control part. Then prototype of 10 kW induction heater was made.
9

Spínaný stejnosměrný laboratorní zdroj 30V 60A / Laboratory DC power supply 30V 60A

Gábel, Marián January 2021 (has links)
The master thesis deals with design of a switched DC power supply with output parameters of 30 V 60 A. The power supply uses the connection of two single switch forward converters with opposite phase. The topology was chosen based on a comparison of specific schematics in the first part. The body of the thesis is covered in chapter which deals with design and analysis of power circuits of the converter. The chapter describes detailed design of pulse transformers, dimensioning of semiconductors and cooling system of the converter. For lower power losses, the system of synchronous rectifying is chosen at the output of the circuit. The regulation of the output is based on cascade structure with a superior voltage and dependent current loop. Appropriate over current protection is provided by sensing the output current and using current transformers for primary current measure.
10

Spínaný napájecí zdroj s planárním transformátorem / Switching Power Supply with Planar Transformer

Pawlas, Andrzej January 2010 (has links)
This master's thesis describes the development of switching power supply with planar transformer. Deals with selection of a suitable integrated circuit together with the topology, a purchase of prototype for the reference measurements and debugging its own power supply. Further design and implementation of planar transformer and in the final implementation, debugging, and measurment's its own prototype. Power supply was fully functional and reached the expected parameters.

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