US 11,901,827 B2
Power conversion device and DC power distribution system
Takaharu Ishibashi, Tokyo (JP); and Takushi Jimichi, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/299,787
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Jan. 21, 2019, PCT No. PCT/JP2019/001658
§ 371(c)(1), (2) Date Jun. 4, 2021,
PCT Pub. No. WO2020/152745, PCT Pub. Date Jul. 30, 2020.
Prior Publication US 2022/0123661 A1, Apr. 21, 2022
Int. Cl. H02M 3/335 (2006.01); H02M 1/00 (2006.01)
CPC H02M 3/33584 (2013.01) [H02M 1/0058 (2021.05)] 15 Claims
OG exemplary drawing
 
1. A power conversion device comprising:
a multiwinding transformer including a primary-side winding and a plurality of secondary-side windings;
a primary-side DC terminal connected to a DC power supply;
a plurality of secondary-side DC terminals;
a primly-side bridge circuit connected between the primary-side DC terminal and the primary-side winding, the primary-side bridge circuit carrying out DC/AC power conversion;
a plurality of secondary-side bridge circuits connected between the plurality of secondary-side windings and the plurality of secondary-side DC terminals, respectively, the plurality of secondary-side bridge circuits carrying out AC/DC power conversion; and
a control device to control the primary-side bridge circuit and the plurality of secondary-side bridge circuits,
the plurality of secondary-side windings including
a first secondary-side winding strongest in magnetic coupling to the primary-side winding, and
a second secondary-side winding weaker in magnetic coupling to the primary-side winding than the first secondary-side winding,
wherein a leakage inductance between the primary-side winding and the second secondary-side winding is greater than a leakage inductance between the primary-side winding and the first secondary-side winding,
the plurality of secondary-side DC terminals including
a first secondary-side DC terminal electrically connected to the first secondary-side winding with a first secondary-side bridge circuit of the plurality of secondary-side bridge circuits being interposed, and
a second secondary-side DC terminal electrically connected to the second secondary-side winding with a second secondary-side bridge circuit of the plurality of secondary-side bridge circuits being interposed, wherein the control device includes
a first controller to control the primary-side bridge circuit so as to provide a first AC voltage having a reference phase,
a second controller to control the first secondary-side bridge circuit so as to provide a second AC voltage having a first phase difference from the reference phase, and
a third controller to control the second secondary-side bridge circuit so as to provide a third AC voltage having a second phase difference from the reference phase, and
the first secondary-side DC terminal and the second secondary-side DC terminal supply output voltages different from each other,
a rated output voltage of the DC power supply is substantially equal to a rated output voltage of the first secondary-side DC terminal, and
a turns ratio between the primary-side winding and the first secondary-side winding is closer to one than a turns ratio between the primary-side winding and the second secondary-side winding.