A dual constant power control for metal induction heating system using series resonant inverters

The paper discusses induction heating system using multiphase power supply using two series resonant inverters which feed mutually coupled working coils for temperature profile uniformity and power inverter segmentation for metal tempering applications. A comparison between a single phase and two phase system is conducted to highlight the merits of the two phase approach considering a constant input power in terms of efficiency, temperature uniformity and flexibility for heat distribution. The study shows that by continually adjusting the current and phase shift in the two supply units, the coupling effects is minimised and the system is able to run under better performances. Simulation and experimental are provided to demonstrate the usefulness of the method.