Patent ID: 9595841
Date: 2017-03-14
CPC Classifications: H02J,H02M,Y02B

Claim:
1. A DC-DC converter comprising: a first switching circuit in which a first smoothing capacitor is connected between DC terminals, and a primary winding is connected between AC terminals; a second switching circuit in which a smoothing inductor and a second smoothing capacitor which are connected in series and connected between DC terminals, and a secondary winging is connected to AC terminals; a transformer providing magnetic coupling between the primary winding to the secondary winding; a voltage clamp circuit, including a clamp capacitor and a clamp switching device which are connected in series, the voltage clamp circuit being connected between the DC terminals of the second switching circuit or between the AC terminals of the second switching circuit and a first end of the second smoothing capacitor; and a controller operating either of a first mode or a second mode, wherein, in the first mode, power inputted between first terminals, which are both terminals of the first smoothing capacitor, is outputted between second terminals, which are both terminals of the second smoothing capacitor, and, in the second mode, power inputted between the second terminals is outputted between the first terminals, wherein, in a third mode, the controller outputs, between the first terminals and/or the second terminals, power discharged from the clamp capacitor by switching the clamp switching device, the third mode being performed between an interruption after the first mode or after the second mode and the second mode performed subsequent to the interruptions, and wherein the second switching circuit further includes: a first switching leg including a first switching device and a second switching device connected in series, and ends of the first switching leg are the DC terminals of the second switching circuit, and a second switching leg connected to the first switching leg in parallel, the second switching leg including a third switching device and a fourth switching device connected in series, and a series junction between the first switching device and the second switching device and a series junction between the third switching device and the fourth switching device are the AC terminals of the second switching circuit.