by Lee Yin-sum. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 55-56.

Thesis (M. Phil.)--University of Hong Kong, 1982.

Thesis (M.E.) -- University of Adelaide, Department of Electrical Engineering, 1978. / Typescript (photocopy).

Thesis (M.Phil.)--University of Hong Kong, 1982. / Also available in print.

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 65 p. : ill., maps (part col.). Includes abstract. Includes bibliographical references.

On-line induction machine condition monitoring techniques have been used widely in the detection of motor broken rotor bars for decades. Research has found that when broken bars occur in the machine rotor, the anomaly of electromagnetic field in the air gap will cause two sideband frequency components presenting in the stator current spectrum. Therefore, identification of these sideband frequencies can be used as a convenient and reliable approach to broken rotor bar fault diagnosis. Discrete Fourier Transform (DFT) is a conventional spectral analysis method used in this application. However, the use of DFT has several limitations. The most important one among them is the restriction of frequency resolution by window length. Due to this limitation, the accuracy of broken rotor bar detection can be highly affected in cases such as light machine load and limited data records. However, Prony's method for spectral analysis has the ability of overcoming the restriction of data window length on the frequency resolution, from which the DFT suffers. Such feature makes Prony's method a promising choice for broken rotor bar diagnosis when the machine is operating under light or varying load, or when only restricted data is available. In this thesis, I have demonstrated the implementation of this technique in the induction motor broken rotor bar detection, revealed its better performance than DFT in terms of maintaining high resolution in frequency domain whilst using a much shorter window, and analyzed the influential factors to the method of Prony Analysis (PA). In this thesis, an induction machine model that includes broken rotor bars is developed using Matlab/Simulink and verified by comparing the experimental and the simulated results. The Prony Analysis method for broken bar diagnosis is implemented and tested using both simulated and measured stator current data. Comparisons between PA and DFT results are presented, clearly indicating improvements of broken bar diagnostics using PA. / Thesis (M.Eng.Sc.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2008

Thesis (M. Phil.)--University of Hong Kong, 1989.

No description available.

Today's societies are critically dependent on the reliable supply of electricity. The reliable operation of large synchronous generators in power stations is therefore of paramount importance. Thus, power utilities are most keenly concerned in taking measures to avoid catastrophic failures and to minimise the impact of generator outages due to faults. Each generator constitutes one of the most expensive single pieces of equipment in the power station. Although they are mostly reliable and generally require minimal maintenance, faults can and do occur with varying degrees of consequences ranging from minor outages to catastrophic failures. / When faults occur, cause-effect relationships need to be identified systematically. This is necessary for having a better understanding of the fault formation mechanisms so that preventive measures can be taken, although sometimes the immediate pressures for returning a generator to service may impede a thorough investigation. / This thesis is borne of the Author's experiences in dealing with large synchronous generators of various sizes and designs. The purpose of this thesis is to report on practical problems in the operation of large synchronous generators and offer advice on remedy. It presents carefully documented cases of faults. These vary from fractured stator conductors and core overheating to cracking of rotor retaining rings and winding short circuits. Symptoms of various faults are discussed along with the extent of damage and remedial solutions. Emphasis is placed on being able to prevent the fault recurrence and prolong the mean time between failures (MTBF). / Thesis (MEngineering(Research))--University of South Australia, 2006.

Thesis (M Eng) -- University of South Australia, 1991