BACKFLOW PREVENTION DEVICE, POWER CONVERTER, MOTOR DRIVE DEVICE, AND REFRIGERATING AND AIR-CONDITIONING DEVICE

摘要

In the present invention, a backflow prevention element (5) that is disposed between a power source (1) and a load (9) and is for preventing the backflow of current from the load (9) side to the power source (1) side, a commutation device (7) for carrying out a commutation operation in which current is made to flow through commutation paths connected in parallel with the backflow prevention element (5), and a control device (100) for determining a time over which to cause the commutation operation to be carried out and causing the commutation device (7) to carry out the commutation operation on the basis of the determined time are provided. Providing a plurality of commutation paths makes it possible to, for example, dispose elements, and the like, having small current capacities on the commutation paths and thereby reduce costs and enhances recovery current reduction reliability through resistance to failure, and the like.