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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

Identification of turbo-alternator voltage regulator parameters

Kaan Quan Hang. January 1973 (has links) (PDF)
No description available.
2

Efficient Energy Transfer for Wireless Devices

Westlund, Arvid, Bernberg, Oskar January 2012 (has links)
This project is intended to findsuitable circuit architecture forefficient power transmission where thepower supply is low.Two circuits will be built. The firstwill receive high AC which correspondsto the voltage created in a piezoelement once subjected to stress fromfoot steps It will deliver 3.3DC.The second circuit will receive low ACwhich will represent voltage receivedfrom a wireless transfer.Due to a failing high voltage powersupply the second circuit was never putto practice. The idea was to send a wavefile through an OP-amplifier to simulatethe voltage from the piezo element. Thevoltage was then rectified and convertedto 3.3DC.Circuit 2 was tested with a frequencygenerator as power supply. The voltagewas transformed, rectified and at lastconverted to 3.3DC through a voltageregulator. Due to lack of deliveredpower from the frequency generator itwas necessary to duty cycle the load tolimit the power dissipation.The power dissipation in the voltageregulator was limited as well byswitching it on and off. When switchedoff a capacitor was charged. When in onmode the capacitor was emptied into thevoltage regulator. / Det här projektet är ämnat att hittalämpliga kretsarkitetkturer för braeffektöverföring där energikällorna ärmycket begränsade.Två kretsar ska byggas. Den första skata emot hög växelspänning motsvarandespänningen som uppkommer i ettpiezoelement vilket utsätts för växlandetryck. I det här fallet trycket från enmänniskas fotsteg. Kretsen ska leverera3.3V likspänning.Den andra kretsen ska ta emot en lågväxelspänning, vilken motsvarar spänningfrån en trådlös överföring, och leverera3.3V.Krets 1 blev aldrig testad på grund avett fallerande högspänningsaggregat.Genom att skicka en wav-fil genom en OPförstärkareskulle en simulerad spänningfrån piezoelementet användas. Därefterskulle spänningen likriktas ochkonverteras ner till 3.3V.Krets 2 testades med en signalgeneratorsom spänningskälla. Spänningentransformerades först upp innan denlikriktades och skickades in i enspänningsreglator för att därefter ge ut3.3V. Med en liten levererad effekt frånsignalgeneratorn var det nödvändigt attbegränsa effektåtgången i lasten genompulsbreddmodulering. Effektåtgången ispänningsreglatorn begränsades ocksågenom att stänga av och på IC:n(spänningsregulatorn). När IC:n varavstängd laddades en kondensator upp somsedan tömdes i IC:n då den aktiveradesigen.
3

A voltage reference using a temperature-dependent current to bias a junction diode

Mastovich, Stefan Noel 04 March 2013 (has links)
Bandgap voltage-reference circuits generate an appropriate amount of a voltage that varies proportionately to absolute temperature (called PTAT), to cancel the complementary to absolute temperature voltage variation (known as CTAT) of a current biased p-n junction diode so that the sum of the two voltages remains constant with respect to temperature. The bandgap voltage of Silicon is approximately 1.1V. It is inconveniently large to generate and use in short-channel circuits where the supply voltage is limited 1.2V. So the idea presented here is to maintain a constant reference voltage of around half the supply voltage (700mV) across a junction diode. A simple circuit for generating the bias current with appropriate temperature dependence for biasing a diode is presented. Simulation results in 55 nanometer technology demonstrate the feasibility of this scheme. The performance that is achievable is a reference voltage with less than 1 percent variation in the temperature range of 0 to 100 degrees C. / text
4

A robust linear multivariable regulator with optimal feedforward /

Gantchev, Peter D. S. January 1980 (has links)
No description available.
5

Identification of turbo-alternator voltage regulator parameters.

Kaan Quan Hang. January 1973 (has links) (PDF)
Thesis (M.E.) -- University of Adelaide, Electrical Engineering Department, 1976.
6

A solid-state voltage regulator for motor-generator sets

Chapel, James Clyde, January 1969 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
7

Reactive reserve management in the operational planning of power systems

Rios Zalapa, Ricardo January 1990 (has links)
No description available.
8

A solid state voltage regulator and exciter for a large power system test model

Bond, John Anthony January 1967 (has links)
This thesis is concerned with the design, construction, and testing of a solid state voltage regulator-exciter-for a new power system test model. The basic elements of a power system, the prime mover and the synchronous generator, are simulated by small laboratory sized machines whose characteristics have been altered by electronic devices. The voltage regulator-exciter consists of a transfer function simulator, a selector-switch for forced or linear-excitation, a field amplifier, a negative resistor for the field circuit and a voltage transducer for closed loop control. Also included are a braking resistor with solid state switching and power and-speed transducers. Transient power system studies have been largely theoretical in nature because of the difficulty and danger in carrying out experimental work on actual power systems. With this model, many important and interesting tests can be easily carried out. Chapter 2 outlines the proposed system while Chapter 3 details the realization and circuitry of the subsystems. The results of the tests described in Chapter 4 are divided into two parts. The first section deals with the testing of each subsystem while the last section, the system as a whole. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
9

A robust linear multivariable regulator with optimal feedforward /

Gantchev, Peter D. S. January 1980 (has links)
No description available.
10

Precision Measurement of High Direct Voltage

de Tourreil, Claude 10 1900 (has links)
<p> This thesis describes a new method to measure high direct voltage of the range of 100 KV to 200 KV with very high accuracy. The principle, based on the capacitive divider method, is presented in the first part. </p> <p>This thesis is, however, principally concerned with the design of the low voltage capacitor of the divider and its accuracy. The investigations made lead to an instrument having the accuracy required, which is 0.1 parts per million. </p> / Thesis / Master of Engineering (MEngr)

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