BIDIRECTIONAL DC/DC CONVERTER

摘要

A bidirectional DC/DC converter includes first and second control circuits, and first and second bridge circuits respectively connected to first and second direct current voltage supplies. In one embodiment variant, when power is supplied from the first direct current voltage supply to the second direct current voltage supply, the first control circuit carries out PFM control of the first bridge circuit at a frequency equal to or lower than the resonance frequency of an LC resonant circuit in accordance with a control amount based on the voltage and current of the second direct current voltage supply. When power is supplied in the other direction, the second control circuit carries out fixed frequency control of the second bridge circuit, using phase shift control or the like, in accordance with a control amount based on the voltage and current of the first direct current voltage supply.

主权项

1. A bidirectional DC/DC converter, comprising:
a first bridge circuit connected to a first direct current voltage supply and formed of a plurality of semiconductor switch elements; a second bridge circuit connected to a second direct current voltage supply and formed of a plurality of semiconductor switch elements; an isolating transformer that isolates the first bridge circuit from the second bridge circuit; and a series resonant circuit connected between an alternating current side of the first bridge circuit and the isolating transformer, wherein the bidirectional DC/DC converter is configured to supply power bidirectionally between the first direct current voltage supply and the second direct current voltage supply by having the first bridge circuit or the second bridge circuit carry out a switching operation; a first detector circuit configured to detect at least a voltage value or a current value of the first direct current voltage supply; a second detector circuit configured to detect at least a voltage value or a current value of the second direct current voltage supply; a first control circuit configured to control the first bridge circuit based on a value detected by the second detector circuit, the first control circuit configured to carry out pulse frequency modulation control of the first bridge circuit at a frequency equal to or lower than a resonance frequency of the series resonant circuit based on a control amount determined in accordance with a value detected by the second detector circuit when power is supplied from the first direct current voltage supply to the second direct current voltage supply; and a second control circuit configured to control the second bridge circuit based on a value detected by the first detector circuit, the second control circuit configured to carry out fixed frequency control of the second bridge circuit based on a control amount determined in accordance with a value detected by the first detector circuit when power is supplied from the second direct current voltage supply to the first direct current voltage supply.