Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2006. / This thesis is about the dynamic control of a permanent magnet assisted reluctance synchronous
machine (PMA RSM). The PMA RSM in this thesis is a 110 kW traction machine and is ideal for the
use in electrical rail vehicles. An application of the dynamic control of the PMA RSM in electrical rail
vehicles is to reduce wheel slip.
The mathematical model of the PMA RSM is derived and explained in physical terms. Two methods
of current control for the PMA RSM are investigated, namely constant field current control (CFCC)
and constant current angle control (CCAC). It is shown that CCAC is more appropriate for the PMA
RSM.
A current controller for the PMA RSM that guarantees stability is derived and given as an analytic
formula. This current controller can be used for any method of current control, i.e. CFCC or CCAC.
An accurate simulation model for the PMA RSM is obtained using results from finite element analysis
(FEA). The accurate model is used in a simulation to verify CCAC. A normal proportional integral
speed controller for the PMA RSM is designed and the design is also verified by simulation.
Practical implementation of the current and speed controllers is considered along with a general
description of the entire drive system. The operation of the resolver (for position measurement) is
given in detail. Important safety measures and the design of the electronic circuitry to give protection
are shown. Practical results concerning current and speed control are then shown.
To improve the dynamic performance of the PMA RSM, a load torque observer with compensation
current feedback is investigated. Two observer structures are considered, namely the reduced state
observer and the full state observer. The derivation of the full state observer and the detail designs of
the observer elements are given. The accurate simulation model of the PMA RSM is used to verify the
operation of the observer structures and to evaluate the dynamic performance. Both observer
structures are implemented practically and practical results are shown.
One method of position sensorless control, namely the high frequency voltage injection method, is
discussed in terms of the PMA RSM. This work is additional to the thesis but it is shown, because it
raises some interesting questions regarding the dynamic control of the PMA RSM.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/2062 |
| Date | 03 1900 |
| Creators | De Kock, Hugo Werner |
| Contributors | Kamper, M. J., University of Stellenbosch. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. |
| Publisher | Stellenbosch : University of Stellenbosch |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | 5812940 bytes, application/pdf |
| Rights | University of Stellenbosch |
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