Abstract: An object is to provide an induction heating method having a high power factor in which when thermal processing is performed through a plurality of heating coils receiving the supply of the current to generate mutual induction. In an induction heating method using an induction heating device that includes self-resonant circuits which feeds currents of equal frequency to a plurality of heating coils receiving the supply of the current to generate mutual induction is connected, wherein adjustment or control is performed to carry out an operation such that a first ratio of a reactance component of a mutual induction impedance to a resistance component of the mutual induction impedance between the adjacent self-resonant circuits and a second ratio of a reactance component of a self-impedance to a resistance component of the self-impedance in the self-resonant circuit are made equal to each other.

Abstract: [Object] An object is to provide an induction heating method having a high power factor in which when thermal processing is performed through a plurality of heating coils receiving the supply of the current to generate mutual induction, it is possible to easily and rapidly perform synchronization control on a coil current and in which when the current is varied, even if the speed of control on the current value is increased, this little affects an inverter phase angle. [Solving means] In an induction heating method using an induction heating device that heats an item to be heated and includes a plurality of self-resonant circuits to which a resonant high-frequency power supply feeding currents of equal frequency to a plurality of heating coils receiving the supply of the current to generate mutual induction is connected, the phases of impedances within a system are made to coincide with each other to minimize the phases.