To solve such a problem that the diode of an inverter circuit is recovered reversely and broken down when a resonance type induction heating apparatus normally performing delay operation performs lead operation due to abnormality of a load, for example.

A power converter comprises a voltage detection circuit which detects the voltage between the main terminals of a semiconductor element, and a voltage comparison circuit which compares a voltage set value and the voltage detection value. The voltage set value and the voltage detection value are compared after the semiconductor element is turned off, and when the voltage set value is larger, semiconductor elements of facing arms constituting upper and lower arms and connected in series with the semiconductor element are not turned on.