A new unity power factor quasi-resonant induction heater
type: CreativeWork
description: This thesis reports an investigation into the design of converters for induction heating systems based upon resonant switch mode power converter techniques. The proposed three phase unity power factor induction heating system consists of two stages of power conversions. The important requirements for each stage of the power conversion of a typical induction heating system working from a three-phase supply are identified. A wide range of power converters which fulfil these requirements are compared and evaluated. From the evaluation, the most applicable converter topologies are selected. Each selected converter class is investigated in great detail to outline their advantages and disadvantages. The first stage consists of a push-pull buck converter connected to a unity power factor rectifier stage. This stage converts the three phase AC mains supply to a required DC value. The second stage, which converters the DC into AC is a single ended resonant inverter system. Analysis of the converters has been made and the design procedure has been formulated. The design procedure allows a strenuous design of each resonant converter for particular converter applications. The final converter design has been simulated using the circuit simulation software packages Design Architect and Accusim to verify the results of analysis. The most important design and construction achievements can be summarised as follows: I A novel push-pull buck quasi-resonant converter with a three-phase rectifier stage has been built and tested. At its maximum operating frequency of 40kHz, the prototype converter delivers an output power of 500W. The converter draws nearly sinusoidal currents from the three-phase mains supply and has an input power factor approaching unity. A secondary stage resonant converter provides AC for the induction heater coil. This AC current flowing in the induction coil creates an alternating electromagnetic field for the workpiece. An induction heating coil has been designed…
abstract: This thesis reports an investigation into the design of converters for induction heating systems based upon resonant switch mode power converter techniques. The proposed three phase unity power factor induction heating system consists of two stages of power conversions. The important requirements for each stage of the power conversion of a typical induction heating system working from a three-phase supply are identified. A wide range of power converters which fulfil these requirements are compared and evaluated. From the evaluation, the most applicable converter topologies are selected. Each selected converter class is investigated in great detail to outline their advantages and disadvantages. The first stage consists of a push-pull buck converter connected to a unity power factor rectifier stage. This stage converts the three phase AC mains supply to a required DC value. The second stage, which converters the DC into AC is a single ended resonant inverter system. Analysis of the converters has been made and the design procedure has been formulated. The design procedure allows a strenuous design of each resonant converter for particular converter applications. The final converter design has been simulated using the circuit simulation software packages Design Architect and Accusim to verify the results of analysis. The most important design and construction achievements can be summarised as follows: I A novel push-pull buck quasi-resonant converter with a three-phase rectifier stage has been built and tested. At its maximum operating frequency of 40kHz, the prototype converter delivers an output power of 500W. The converter draws nearly sinusoidal currents from the three-phase mains supply and has an input power factor approaching unity. A secondary stage resonant converter provides AC for the induction heater coil. This AC current flowing in the induction coil creates an alternating electromagnetic field for the workpiece. An induction heating coil has been designed…
author: Sazak, Bekir Sami
language: eng
date published: 1997
date modified: 2026-07-24T04:38:39Z
provider: University of South Wales
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of South Wales