Novel, three phase, unity power factor modular induction heater

Derivation and synthesis of a generic, system-level, macromodel of an induction heater module is presented. The macro-model includes detailed descriptions of discrete cycle-by-cycle commutation events in a soft-switched voltage source inverter, together with the resonant load behaviour. The model facilitates accurate rating of the active switching components with regard to device utilisation and stresses. It is shown that a novel, modular multiphase induction heater system can be constructed, that draws sinusoidal supply currents from the utility supply. Simulation of the module operation in a multiphase system is described, together with experimental validation of the results.