Thesis MTech(Electrical Engineering))--Cape Peninsula University of Technology, 2006 / Reluctance Synchronous Machines (RSM) have, due to their rotor geometry, an inherently
high torque ripple. This torque ripple is defined as the deviation of the minimum and
maximum torque from the average value. It is unwanted as it indicates uneven pull on the
rotor causing deformation of it and hence different air-gaps along the rotor circumference
as well as acoustic noise. In applications such as power steering, robotics and radar
positioning systems where high precision movement is vital, oscillating torque will lead to
the malfunction of these devices and therefore suppressed the use and development of
RSMs.
Unlike the Induction machine (IM), the RSM has no copper losses in the rotor, which
reduces the operating temperature significantly. With the development of electronic drives
the quality of the output torque could be improved by means of accurate current- and flux
space phasor control methods with much success and made the RSM a possible
replacement for the IM. However, reducing torque ripple by means of purely geometrical
changes is still a challenge to the machine designer.
This thesis will focus on the reduction of torque ripple while leaving the average torque
relatively unchanged by changing the rotor geometry. The rotor changes will take place by
means of flux barriers and cut-outs while the stator has either semi-closed slots or magnetic
wedges.
In this work rotor structures with equal harmonic magnitudes but their angles 1800 apart.
will be combined to form one machine and identify how torque harmonics respond. The
change in average torque and power factor will be evaluated with all geometrical changes
made to these machines throughout this work.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:cput/oai:localhost:20.500.11838/1145 |
| Date | January 2006 |
| Creators | Hanekom, Alwyn Nicolaas |
| Publisher | Cape Peninsula University of Technology |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Rights | http://creativecommons.org/licenses/by-nc-sa/3.0/za/ |
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