DC POWER SUPPLY DEVICE, ELECTRIC MOTOR DRIVE DEVICE EQUIPPED WITH SAID DC POWER SUPPLY DEVICE, AND REFRIGERATING CYCLE DEVICE EQUIPPED WITH SAID ELECTRIC MOTOR DRIVE DEVICE

摘要

A DC power supply device is configured such that, on the input side of a rectifier circuit (2) for rectifying AC power (AC power supply (1) side), a first reactor (3) is provided and, on the output side (load (11) side), first and second capacitors (6a, 6b) connected in series and first and second switching elements (4a, 4b) for switching between charging and non-charging of the first and second capacitors (6a, 6b) are provided. In this configuration, a Y-connected second capacitor group (9) equipped with three capacitors connected to the respective phase terminals of the first reactor (3) on the rectifier circuit (2) side is connected to the midpoint between the first and second switching elements (4a, 4b), and the output voltage to a load (11) is boosted while performing control so that the on-duties of the first and second switching elements (4a, 4b) become equal to each other.