The Induction Heating Power Supply With A Power Factor Correction

In the early20th century, Induction heating technology was used widely in industry.With the rapid development of power electronic devices and the technology, induction heating technology has made great progress. At present, the induction heating technology, with its fast heating,high efficiency and controllability superior performance,has been widely used in all walks of life in the national economy. In this paper, a power factor correction of induction heating power supply with the primary series resonant circuit topology has produced successfully.This front-end circuit employs a boost-type power factor correction circuit, and post-stage is a series resonant circuit as the main circuit topology of the induction heating power supply. Front-end circuit uses a UC3854BN chip with power factor correction to complete PFC boost function at an average current control mode,which provides a stable output voltage310V for the post-stage circuit. The main circuit topology of post-stage circuit adopts the series resonant inverter and uses phase-locked loop HEF4046B chip as the controll core, including the power adjustment circuit, phase-limited circuit current regulator, to achieve a PFM (frequency modulation) control of the induction heating power supply.Finally, an experimental prototype is completed, and the system key points of the waveform is tested. The debugging results of the experiment show that a series resonant inverter for closed-loop works well, switches can all achieve zero voltage switching. Pre-power-factor correction circuit makes the input current follow the input voltage changes rapidly, which can effectively inhibit the harmonic currents, improve the system’s anti-jamming capability and the power factor.