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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.
71

Development of a 300 Hp regenerative motor and generator test facility

Lewis, Timothy M. 19 June 1995 (has links)
A 300 hp motor and generator testing facility is being completed at Oregon State University. The testing center is the largest independent testing facility west of the Mississippi River. This regional resource center will incorporate state-of-the-art features that set it apart from other testing facilities. An induction machine with a modem regenerative power electronic converter is being used as the dynamometer. This regenerative dynamometer system significantly reduces the amount of power necessary for testing, allows for extremely flexible computer controlled testing, and is able to test adjustable speed machine systems from 100-4000 r/min. The dynamometer system is able to fully test both motors and generators of 240 hp from no-load to 125% rated load. A virtual instrumentation system provides tremendous flexibility and measures instantaneous, rms, and spectral signal values. Because the system is designed for testing over a wide speed range, it is necessary that all dynamometer losses are isolated and tabulated for the entire speed range. Initial fixed speed testing was performed on a 60 hp induction motor and standard report formats were generated for this and future test center use. The results were compared to the manufacturer's original testing data. To demonstrate the ability to test generators by using the dynamometer as a prime mover, a set of tests were also performed on a synchronous machine in accordance with IEEE standards. / Graduation date: 1996
72

General pole number model for the brushless doubly-fed machine

Boger, Michael S. 06 July 1994 (has links)
The Brush less Doubly-Fed Machine (BDFM) has the potential to be a more cost effective replacement for conventional induction or synchronous machine drives. The BDFM has two stator windings: a power winding and a control winding. An electronic power converter of variable voltage and frequency is connected to the control winding and allows the speed of the machine to be adjusted synchronously. The power winding, by design, carries the majority of the current needed for operation, the control winding only a fraction of the current, thus enabling the converter rating to be as low as 25% of the rating of the machine depending on the speed range of operation. To date, only one specific stator pole-pair combination has been investigated, namely the 3/1 combination, where 3 and 1 refer to the power winding pole-pairs and the control winding pole-pair, respectively. Since the speed of the machine is dependent on the sum of the pole-pairs of the stator windings, a general pole numbered model is needed to evaluate the performance of such general machines with other pole-pair number machines. The BDFM describing system equations are transformed to the two axis (dq) rotor reference frame using a power invariant transformation. The analysis shows an additional term involving the common bar impedance which was not present in earlier analyses. The dynamic model is simplified to yield a steady state synchronous model. The synchronous frequency of analysis is investigated which results in two equivalent steady state models. The models developed can easily handle excitation of any frequency or sequence on the control winding without the use of an auxiliary model as used in previous analyses. The voltage forced model predictions match data taken for a 5 hp BDFM laboratory prototype, establishing the validity of the analysis. The model is used in illustrating the torque producing capabilities and unity power factor operation of the machine under a variety of inputs. Using the model, predictions are made on a different pole-pair combination machine (4/2 BDFM) for use as a 60 hp pump drive as an alternative to a 3/1 BDFM for the same application. / Graduation date: 1995
73

A unified modulation scheme for three-phase inverter-fed induction motor drives /

Thirugnanasambandamoorthy, Madusudanan, January 2001 (has links)
Thesis (M.Eng.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 113-117.
74

Bearing damage detection via wavelet packet decomposition of stator current /

Eren, Levent, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 96-99). Also available on the Internet.
75

Bearing damage detection via wavelet packet decomposition of stator current

Eren, Levent, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 96-99). Also available on the Internet.
76

Control of chaos in advanced motor drives

Gao, Yuan, 高源 January 2005 (has links)
published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy
77

Harmonic effects in rotating electrical machines.

Fahmy, Mona Samaha- January 1973 (has links)
No description available.
78

Sensorless stator winding temperature estimation for induction machines

Lee, Sang-Bin 05 1900 (has links)
No description available.
79

Exact feedback linearization with state derivative feedback for high-performance field-oriented induction motor speed/position control

Boukas, Theocharis K. 05 1900 (has links)
No description available.
80

The application of cyclostationary signal processing techniques to fault detection in electrical machines

Pourbeik, Peyam January 1999 (has links)
Thesis (PhD)--University of South Australia, 1999

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