전류원 PWM 정류기 / 인버터를 이용한 단조용 유도가열 전원장치의 전원회로 및 제어회로 설계

Abstract

Induction heating can convert electrical energy to thermal energy with high conversion efficiency and quick heating. Currently, a current source rectifier/inverter-fed parallel resonant circuit is widely used as an induction heating power supply for forging applications. However, the conventional thyristor current source rectifier/inverter-fed parallel resonant circuit widely used for induction heating of forging applications has low power factor and high THD at the input side. Because of these disadvantage the IGBT PWM current source rectifier and inverter has been recently studied as an induction heating power supply topology. Therefore, this paper proposes the design guide line of the IGBT PWM current source rectifier and inverter, the design method of power factor controller, the new detecting method of current and voltage for use in system control, and also the technique to follow the resonance voltage of the tank circuit for inverter switching. The proposed techniques are implemented in a 40kVA induction heating power supply and its performances are verified through experiments. It is expected to be used extensively in induction heating power supply systems for forging with wide power range.