US 12,176,752 B2
Uninterruptible power supply system
Yuki Yamashita, Chuo-ku (JP); and Tomohiro Tanaka, Chuo-ku (JP)
Assigned to TMEIC Corporation, Chuo-ku (JP)
Appl. No. 17/907,726
Filed by TMEIC Corporation, Chuo-ku (JP)
PCT Filed Jul. 3, 2020, PCT No. PCT/JP2020/026201
§ 371(c)(1), (2) Date Sep. 29, 2022,
PCT Pub. No. WO2022/003954, PCT Pub. Date Jan. 6, 2022.
Prior Publication US 2023/0134153 A1, May 4, 2023
Int. Cl. H02J 9/06 (2006.01); H02J 3/32 (2006.01); H02M 1/42 (2007.01); H02M 3/335 (2006.01)
CPC H02J 9/062 (2013.01) [H02J 3/32 (2013.01); H02J 9/068 (2020.01); H02M 1/42 (2013.01); H02M 3/33584 (2013.01); H02J 2207/20 (2020.01)] 3 Claims
OG exemplary drawing
 
1. An uninterruptible power supply system comprising:
a plurality of uninterruptible power supplies connected in parallel between an AC power supply and a load; and
a control device that controls the plurality of uninterruptible power supplies,
the plurality of uninterruptible power supplies each including
a first switch connected between the AC power supply and an AC node, and
a power conversion device configured to selectively receive power from one of the AC node and a power storage device, generate AC power, and supply the AC power to the load, wherein
the control device sets the plurality of uninterruptible power supplies to a first power feeding mode while the AC power supply is normal, and sets the plurality of uninterruptible power supplies to a second power feeding mode when the AC power supply fails,
during the first power feeding mode, the control device turns on the first switch, and controls the power conversion device so as to receive AC power from the AC node and generate AC power,
during the second power feeding mode, the control device turns off the first switch, and controls the power conversion device so as to receive DC power from the power storage device and generate AC power,
when the AC power supply recovers during the second power feeding mode, the control device successively switches the plurality of uninterruptible power supplies to the first power feeding mode by successively turning on a plurality of the first switches each of which corresponds to each of the plurality of uninterruptible power supplies, wherein
the power conversion device includes
a converter having the AC node, and a DC node that receives DC power from the power storage device, that selectively receives power from one of the AC node and the DC node and generates DC power,
an inverter that converts DC power supplied from the converter into AC power and supplies the AC power to the load, and
a second switch connected between the power storage device and the DC node,
during the first power feeding mode, the control device turns on the first switch, and turns off the second switch,
during the second power feeding mode, the control device turns off the first switch, and turns on the second switch, and
when the AC power supply recovers during the second power feeding mode, the control device successively switches the plurality of uninterruptible power supplies to the first power feeding mode by successively turning on the plurality of first switches and successively turning off a plurality of the second switches each of which corresponds to each of the plurality of uninterruptible power supplies.