Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines

Thesis (PhD (Electric and Electronic Engineering))--University of Stellenbosch, 2006.

Saved in:
Bibliographic Details
Main Author: Rakgati, Edward Tshitshiri
Other Authors: Kamper, M. J.
Format: Thesis
Language:English
Published: Stellenbosch : University of Stellenbosch 2008
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613736985952256
access_status_str Open Access
author Rakgati, Edward Tshitshiri
author2 Kamper, M. J.
author_browse Kamper, M. J.
Rakgati, Edward Tshitshiri
author_facet Kamper, M. J.
Rakgati, Edward Tshitshiri
author_sort Rakgati, Edward Tshitshiri
collection Thesis
dc_rights_str_mv University of Stellenbosch
description Thesis (PhD (Electric and Electronic Engineering))--University of Stellenbosch, 2006.
format Thesis
id oai:scholar.sun.ac.za:10019.1/1107
institution Stellenbosch University (South Africa)
language English
last_indexed 2026-06-10T12:40:53.839Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository
publishDate 2008
publishDateRange 2008
publishDateSort 2008
publisher Stellenbosch : University of Stellenbosch
publisherStr Stellenbosch : University of Stellenbosch
record_format dspace
source_str SUNScholar — Stellenbosch University Repository
spelling oai:scholar.sun.ac.za:10019.1/1107 Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines Rakgati, Edward Tshitshiri Kamper, M. J. University of Stellenbosch. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. Theses -- Electrical engineering Dissertations -- Electrical engineering Reluctance motors Electrical and Electronic Engineering Thesis (PhD (Electric and Electronic Engineering))--University of Stellenbosch, 2006. The focus of this thesis is on the critical evaluation of the torque performance of the optimum designed reluctance DC machine (RDCM). The thesis focuses on multi-phase RDCM drives with normal laminated salient pole rotors allowing for high power and high-speed applications. An RDCM is a normal reluctance synchronous machine (RSM) but with direct control of flux and torque just as in brush DC machines. Flux and torque of the RDCM are controlled directly by the use of special phase current waveforms. Specific attention is given in the thesis for the selection of the best current waveform for the RDCM allowing for smooth rotating airgap MMF and less ripple torque. The absolute optimum designed RDCM can best be obtained by the use of the finite element (FE) method in the design optimisation process. In this thesis a multi-dimensional FE based design optimisation method for the optimum design of the current controlled RDCM is implemented. To compare the torque performance of the RDCM with other RSMs the torque performances of optimum designed 3-phase, 5-phase and 5-phase with the injection of third harmonic current RSMs are performed under the same copper losses and stack volume. The torque performances of RSMs are done with both salient pole rotor and the round rotor with internal flux barriers. The armature reaction effect of 6-phase RDCMs is also investigated in detail by considering three different rotor structures. These rotor structures are the standard salient pole rotor, the salient pole rotor with slitted poles and the salient pole rotor with chamfered poles. It was shown that the RDCM with the salient pole rotor has a severe armature reaction effect, which can be reduced by slitted or chamfered salient pole rotors. A per-phase equivalent circuit model of the 6-phase RDCM is also proposed in this thesis. The torque of the machine is calculated based on the per-phase equivalent model and compared with the torque calculated by the FE Maxwell stress tensor method. There is a good agreement between these calculated torques. This thesis shows that the implemented FE based optimisation method can be applied with success to optimally design current controlled RDCMs. It was found, amongst other things, that the torque performance of the optimum designed 6-phase RDCM is slightly higher than that of the optimum designed 5-phase RSM with the injection of 3rd harmonic currents and with the same copper losses and stack volume. The analytical and FE calculated results are confirmed by measured results on a 35 kW 6-phase RDCM drive. Doctoral 2008-07-24T12:39:57Z 2010-06-01T08:12:39Z 2008-07-24T12:39:57Z 2010-06-01T08:12:39Z 2006-12 Thesis http://hdl.handle.net/10019.1/1107 en University of Stellenbosch application/pdf Stellenbosch : University of Stellenbosch
spellingShingle Theses -- Electrical engineering
Dissertations -- Electrical engineering
Reluctance motors
Electrical and Electronic Engineering
Rakgati, Edward Tshitshiri
Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines
title Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines
title_full Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines
title_fullStr Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines
title_full_unstemmed Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines
title_short Torque Performance of Optimally Designed Multi-Phase Reluctance DC Machines
title_sort torque performance of optimally designed multi phase reluctance dc machines
topic Theses -- Electrical engineering
Dissertations -- Electrical engineering
Reluctance motors
Electrical and Electronic Engineering
url http://hdl.handle.net/10019.1/1107
work_keys_str_mv AT rakgatiedwardtshitshiri torqueperformanceofoptimallydesignedmultiphasereluctancedcmachines