Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Includes bibliographical references.
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | English |
| Published: |
Department of Electrical Engineering
2016
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613337452281856 |
|---|---|
| access_status_str | Open Access |
| author | Khan, Irshad |
| author2 | Tapson, Jonathan |
| author_browse | Khan, Irshad Tapson, Jonathan |
| author_facet | Tapson, Jonathan Khan, Irshad |
| author_sort | Khan, Irshad |
| collection | Thesis |
| description | Includes bibliographical references. |
| format | Thesis |
| id | oai:open.uct.ac.za:11427/17437 |
| institution | University of Cape Town (South Africa) |
| language | eng |
| last_indexed | 2026-06-10T12:34:32.198Z |
| license_str | Not specified — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository |
| publishDate | 2016 |
| publishDateRange | 2016 |
| publishDateSort | 2016 |
| publisher | Department of Electrical Engineering |
| publisherStr | Department of Electrical Engineering |
| record_format | dspace |
| source_str | UCTD — University of Cape Town Open Access Repository |
| spelling | oai:open.uct.ac.za:11427/17437 Analysis and design of a high frequency induction-heating system Khan, Irshad Tapson, Jonathan Electrical Engineering Includes bibliographical references. Advances in power electronic semiconductor technology are making high frequency converters for induction heating more feasible at power levels up to 50kW. This research presents the development and analysis of a solid-state induction-heating system, operating directly off single-phase mains frequency, which enables optimum and efficient operation over a frequency range of 80kHz to 200kHz. The system essentially comprises a DC-DC converter configured as a controlled current source, which feeds a load resonant DC-AC inverter, driving a parallel resonant load circuit. The load circuit comprises an induction-heating coil and a reactive power compensating capacitor. The systems active switching elements comprise power MOSFET's but can be extended to almost any other controlled power devices such as IGBT's, BJT's, SCR's, GTO's or SIT's. An automatic frequency control system ensures that the DC-AC inverter drives the load at its resonant frequency, thereby achieving zero voltage switching of the power semiconductors. This operating mode always ensures maximum power transfer to the load as well as maximum operating efficiency of the DC-AC inverter. Driving the load at resonance presents an essentially resistive load to the DC-DC converter, thereby reducing the losses associated with a reactive load. A compact circuit layout combined with this optimum mode of operation eliminates the need for any snubber circuit components in both the DC-DC and DC-AC converters at this power level. An overview into various applications and technologies of induction-heating is presented in this research. A detailed analysis of the induction-heating coil and work- piece are presented in order to aid the design of the load circuit. The induction-heating technology overview presents various induction-heating power sources, discussing the configurations of various topologies. A brief mathematical analysis is used to describe the operation of power electronic converters employed in the induction-heating system developed for this research. The parallel resonant induction-heating load circuit is characterised mathematically, allowing for the determination of the optimum operating conditions. This is followed by a simulation analysis, which is used to gain insight into the problem of frequency control. The frequency control system is modelled and the steady-state error response evaluated under different input conditions. Experimental results on the system implemented, based on operating waveforms and efficiency measurements of the solid-state induction-heating system are presented along with recommendations for future work. The implemented power source was tested at a maximum power of 2.3kW at 151kHz. A system efficiency of 86% at 1.3kW was measured when operating at 138kHz. This design however, provides for scaling to power levels up to 50kW. The induction-heating system's frequency tracking capability is evaluated by heating a steel work-piece through its Curie transition temperature. The induction-heating system is used to heat a 26mm x 35mm stainless-steel billet (work-piece) to 1200°C in 130 seconds using the calculated power of 1.35kW . 2016-03-04T16:32:24Z 2016-03-04T16:32:24Z 2003 Master Thesis Masters MSc http://hdl.handle.net/11427/17437 eng application/pdf Department of Electrical Engineering Faculty of Engineering and the Built Environment University of Cape Town |
| spellingShingle | Electrical Engineering Khan, Irshad Analysis and design of a high frequency induction-heating system |
| thesis_degree_str | Master's |
| title | Analysis and design of a high frequency induction-heating system |
| title_full | Analysis and design of a high frequency induction-heating system |
| title_fullStr | Analysis and design of a high frequency induction-heating system |
| title_full_unstemmed | Analysis and design of a high frequency induction-heating system |
| title_short | Analysis and design of a high frequency induction-heating system |
| title_sort | analysis and design of a high frequency induction heating system |
| topic | Electrical Engineering |
| url | http://hdl.handle.net/11427/17437 |
| work_keys_str_mv | AT khanirshad analysisanddesignofahighfrequencyinductionheatingsystem |