Patent ID: 8908405

Claim:
An inverter comprising an inversion unit for converting a direct current bus voltage into an alternating current voltage, the inversion unit including a first external switch, a first internal switch, a second internal switch, and a second external switch which are connected in series in order between a direct current bus positive voltage terminal and a direct current bus negative voltage terminal, a first snubber unit connected between the direct current bus negative voltage terminal and the first internal switch, the first snubber unit being used for suppressing voltage stress of the first internal switch, and a second snubber unit connected between the direct current bus positive voltage terminal and the second internal switch, the second snubber unit being used for suppressing voltage stress of the second internal switch, wherein the first snubber unit includes a first snubber branch connected in parallel with the first internal switch and a first discharge unit connected between the first snubber branch and the direct current bus negative voltage terminal, the second snubber unit includes a second snubber branch connected in parallel with the second internal switch and a second discharge unit connected between the second snubber branch and the direct current bus positive voltage terminal, the first snubber branch includes a first snubber capacitor and a first snubber diode connected in series, the second snubber branch includes a second snubber capacitor and a second snubber diode connected in series, the first discharge unit includes a first discharge diode connected between a node connected between the first snubber capacitor and the first snubber diode and the direct current bus negative voltage terminal, and the second discharge unit includes a second discharge diode connected between a node connected between the second snubber capacitor and the second snubber diode and the direct current bus positive voltage terminal.