D.Ing. / In this thesis, contactless power transmission with sliding transformers to mobile loads is investigated. The sliding transformer comprises an extended primary winding - placed along the path of travel - which is fed through a core containing a secondary winding and which is attached to a mobile load. In the first chapter problems with existing power supply systems are discussed whereafter several possible applications of such a system are identified. In this chapter different methods of obtaining contactless power transmission are also discussed and a brief discussion of a practical, cost effective system is given. In chapter two the application of different resonant topologies to compensate the large structural inductance of the sliding transformer is investigated. A Series Resonant, Series Loaded topology is identified as the most practical and efficient topology for this application and a more detailed analysis of this topology - as applied to this case - is given. Formulas to calculate the sliding transformer parameters are given in the third chapter and two quantities relating the optimization of sliding transformers to the parameters thereof, are defined. Methods to optimize sliding transformers in terms of these two quantities, and also with respect to EMI, are also discussed in this chapter. The design of a five meter long experimental system which delivers 15 kVA to a mobile load is given in chapter four and experimental results of this system are presented. In chapter five a detailed investigation into different output power control methods is conducted. The effect of these control methods on EMI is investigated by means of numerical simulation of a Series Resonant, Series Loaded system under these different control methods. The most complex control method which generates the most EMI, namely frequency and pulse burst control, is implemented into the experimental system to investigate the limitations thereof. Experimental results of this controlled system are presented. It is found that this control method increases the control range obtainable with classical frequency control but introduces many limitations due to discontinuous primary current. It is concluded in the last chapter that it is possible to optimize sliding transformers within achievable cost constraints to such an extent that such systems have acceptable efficiencies and that reasonable system lengths are obtainable.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uj/uj:7412 |
| Date | 27 November 2012 |
| Creators | Barnard, Jacobus Marthinus |
| Source Sets | South African National ETD Portal |
| Detected Language | English |
| Type | Thesis |
Page generated in 0.0021 seconds