DC-DC converter

摘要

A first switching circuit is connected between a transformer first winding and a DC power supply. A second switching circuit is connected between the transformer second winding and a battery. When charging the battery, a control circuit turns off an element in a second bridge circuit in the second switching circuit, and controls a phase shift amount of a first diagonal element, and a phase shift amount of a second diagonal element in the second bridge circuit, relative to a drive phase of a first reference element in a first bridge circuit in the first switching circuit. When discharging the battery, the control circuit turns off an element in the first bridge circuit and controls a phase shift amount of the second diagonal element and a phase shift amount of the first diagonal element relative to a drive phase of a second reference element in the second bridge circuit.

主权项

1. A DC-DC converter which performs bidirectional power transmission between a first DC power supply and a second DC power supply, the DC-DC converter comprising:
a transformer; a first converter unit composed of a full-bridge circuit having two bridge circuits each having a plurality of semiconductor switching elements to each of which an antiparallel diode and a parallel capacitor are connected, the first converter unit being connected between the first DC power supply and a first winding of the transformer, and performing bidirectional power conversion between DC and AC; a second converter unit composed of a full-bridge circuit having two bridge circuits each having a plurality of semiconductor switching elements to each of which an antiparallel diode and a parallel capacitor are connected, the second converter unit being connected between the second DC power supply and a second winding of the transformer, and performing bidirectional power conversion between DC and AC; a first reactor and a second reactor connected on respective AC input/output lines of the first converter unit and the second converter unit; and a control circuit for drive-controlling each semiconductor switching element in the first converter unit and the second converter unit, thereby controlling the first converter unit and the second converter unit, wherein in first power transmission from the first DC power supply to the second DC: power supply, the control circuit
turns off all the semiconductor switching elements of a second bridge circuit which is one of the bridge circuits of the second converter unit,controls each semiconductor switching element in the first converter unit so as to perform zero voltage switching, using the first reactor, andwhen voltage of the second DC power supply is higher than voltage generated on the second winding of the transformer, controls the second converter unit so as to perform step-up operation, using the second reactor, and in second power transmission from the second DC power supply to the first DC power supply, the control circuit
turns off all the semiconductor switching elements of a first bridge circuit which is one of the bridge circuits of the first converter unit,controls each semiconductor switching element in the second converter unit so as to perform zero voltage switching, using the second reactor, andwhen voltage of the first DC power supply is higher than voltage generated on the first winding of the transformer, controls the first converter unit so as to perform step-up operation, using the first reactor.