Semiconductor switch having reverse voltage application circuit and power supply device including the same

摘要

According to one embodiment, a semiconductor switch includes a main element including a switching element and an antiparallel diode, and a reverse voltage application circuit. The reverse voltage application circuit includes an auxiliary electric-power supply, a high-speed free wheeling diode, an auxiliary element, and a capacitor. The high-speed free wheeling diode comprises a plurality of diodes connected in series.

主权项

1. A semiconductor switch to be provided in a power conversion device and to be connected in series to a second semiconductor switch between a positive line and a negative line of the power conversion device, the semiconductor switch comprising:
a main element including a voltage-drive-type switching element and an antiparallel diode connected in anti-parallel with the switching element; and a reverse voltage application circuit which is connected in parallel with the main element, and which includes a high-speed free wheeling diode, a capacitor, and an auxiliary element; wherein: the high-speed free wheeling diode comprises a plurality of diodes connected in series to each other, and has a reverse recovery time which is shorter than a reverse recovery time of the antiparallel diode, and a reverse recovery charge which is smaller than a reverse recovery charge of the antiparallel diode; the capacitor is connected in parallel to a power supply; the auxiliary element is turned on at a dead time set before the second semiconductor switch is turned on; and the high-speed free wheeling diode, the capacitor, and the auxiliary element are connected in series to each other.