×

DC power-supply device and refrigeration cycle device

  • US 9,816,737 B2
  • Filed: 10/29/2013
  • Issued: 11/14/2017
  • Est. Priority Date: 10/29/2013
  • Status: Active Grant
First Claim
Patent Images

1. A DC power-supply device that converts an alternating current from a three-phase AC power supply into a direct current and supplies the converted current to a load, the DC power-supply device comprising:

  • a rectifier circuit that has a reactor connected to an input side or an output side thereof and that rectifies the alternating current from the three-phase AC power supply;

    a first capacitor and a second capacitor that are connected in series between output terminals to the load;

    a charging unit that selectively charges one or both of the first capacitor and the second capacitor; and

    a control unit that controls the charging unit, wherein;

    the charging unit includes;

    a first switching element and a second switching element that are connected in series and are switched at a frequency that is a multiple n (where n is a natural number) of a frequency of the three-phase AC power supply,a first backflow prevention element that prevents backflow of a stored electric charge of the first capacitor to the first switching element, anda second backflow prevention element that prevents backflow of a stored electric charge of the second capacitor to the second switching element,a point between the first switching element and the second switching element and a point between the first capacitor and the second capacitor are connected to each other,the DC power-supply device further comprises a power-supply voltage detection unit,the control unit controls an operation mode,the operation mode includes;

    a full-wave rectification mode in which the first switching element and the second switching element are always turned off and on-duty ratios of the first switching element and the second switching element are 0%, anda boosting mode in which the first switching element and the second switching element are alternately turned on at a charging frequency, andin the boosting mode, an output voltage is controlled by gradually increasing the on-duty ratios of the first switching element and the second switching element.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×