Patent ID: 9531250
Filing Date: 2016-12-27
CPC Classification: H02M,Y02B

Claim Text:
1. A power conversion device comprising: a power supply unit; a booster unit that boosts a voltage supplied from the power supply unit by switching control; a smoothing unit that smoothes an output voltage from the booster unit; a backflow prevention element that is arranged between the booster unit and the smoothing unit to prevent a current reverse flow toward the booster unit; a commutation unit that is connected to the backflow prevention element in parallel to commutate a current flowing through the backflow prevention element in a predetermined period before a short-circuit current begins to flow in response to the switching control of the booster unit; and a determination unit that determines a duty ratio of the switching control and an implementation period of a commutation operation by the commutation unit, based on a plurality of thresholds and a comparison target signal that is a triangle-wave signal or a sawtooth signal, wherein the thresholds include a first threshold, a second threshold that is equal to or larger than the first threshold, and a third threshold that is equal to or smaller than the first threshold, and the determination unit determines the duty ratio based on a comparison result between the first threshold and the comparison target signal, and determines the implementation period based on a comparison result between the third threshold and the comparison target signal.