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Document Description
TitleA universal controller for a single-phase uninterruptible power supply system
AuthorCheng, Limin, 1967-
DescriptionThesis (M. Eng.), Memorial University of Newfoundland, 1999. Engineering and Applied Science
Pagination130 leaves : ill.
SubjectElectronic controllers; Uninterruptible power supply
DegreeM. Eng.
Degree GrantorMemorial University of Newfoundland. Faculty of Engineering and Applied Science
DisciplineEngineering and Applied Science
NotesBibliography: p. 113-115
AbstractIn this thesis, a single-phase voltage-source uninterruptible power supply (UPS) for 60Hz and 400 Hz applications is discussed. Two control strategies, namely a two-loop controller and a three-loop controller are developed. The control systems developed in this thesis have the following features: (1) stable operation at 60Hz and 400Hz, (2) no need of an external current signal. (3) high output quality, and (4) fast dynamic response. To meet these specifications, dynamic models which take into consideration the feedback variables and switching function are developed. Two suitable PI controllers for the current and voltage loops are selected according to frequency response analysis. Meanwhile, second-order feedback filters are designed to guarantee a perfect output waveform. As a result, the two-loop controller employs the output filter capacitor current and the load voltage as feedback variables while the three-loop controller uses the inverter output current as the third feedback variables. -- SIMULINK. models of the proposed controllers are implemented, and the steady-state and dynamic response, THD of the output voltage and voltage utilization are presented at the two standard frequencies of 60Hz and 400Hz. It is shown from the simulation results that the performance of the controllers meets the requirements. Moreover, computer simulation results of the output voltage waveform, the total harmonic distortion, voltage utilization and dynamic response show that the three-loop controller has a better performance.
FormatImage/jpeg; Application/pdf
SourcePaper copy kept in the Centre for Newfoundland Studies, Memorial University Libraries
Local Identifiera1355611
RightsThe author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission.
CollectionElectronic Theses and Dissertations
Scanning StatusCompleted
PDF File(11.72 MB) --
CONTENTdm file name109905.cpd