US 12,170,487 B2
Insulating transformer and power conversion device equipped with same
Yuki Itogawa, Tokyo (JP); Kikuo Izumi, Tokyo (JP); Takeshi Amimoto, Tokyo (JP); Yu Kawai, Tokyo (JP); and Tomoaki Kimura, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/766,534
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Dec. 5, 2019, PCT No. PCT/JP2019/047679
§ 371(c)(1), (2) Date Apr. 5, 2022,
PCT Pub. No. WO2021/111601, PCT Pub. Date Jun. 10, 2021.
Prior Publication US 2023/0208304 A1, Jun. 29, 2023
Int. Cl. H02M 3/335 (2006.01); H01F 38/08 (2006.01); H02M 1/44 (2007.01); H01F 38/00 (2006.01)
CPC H02M 3/33584 (2013.01) [H01F 38/08 (2013.01); H02M 1/44 (2013.01); H01F 2038/006 (2013.01)] 2 Claims
OG exemplary drawing
 
1. An insulating transformer comprising:
first to Nth sub-insulating transformers electrically coupled to each other, N being an integer greater than or equal to 2, wherein each of the first to Nth sub-insulating transformers includes:
first and second sub-windings;
first and second sub-terminals connected to a first polarity terminal and a second polarity terminal of the first sub-winding, respectively; and
third and fourth sub-terminals connected to a first polarity terminal and a second polarity terminal of the second sub-winding, respectively,
polarity directions of the first and second sub-windings are identical,
the first sub-winding of each of the first to Nth sub-insulating transformers and the second sub-windings of each of the first to Nth sub-insulating transformers are electrically insulated from each other except for an interphase capacitance,
each of the first to Nth sub-insulating transformers is configured such that an excitation inductance of the first sub-winding and an excitation inductance of the second sub-winding become opposite polarities when a current flows from the first sub-terminal to the third sub-terminal through the first sub-winding, the interphase capacitance between the first and second sub-windings, and the second sub-winding,
each of the first to Nth sub-insulating transformers includes an iron core, the first and second sub-windings of each of the first to Nth sub-insulating transformers are being wound around the respective iron core, and
the iron core of each of the first to the Nth sub-insulating transformers are separated from each other,
wherein
the insulating transformer comprises:
first and second main windings;
first and second main terminals connected to a first polarity terminal and a second polarity terminal of the first main winding, respectively; and
third and fourth main terminals connected to a first polarity terminal and a second polarity terminal of the second main winding, respectively,
polarity directions of the first and second main windings are identical,
the polarity directions of the N first sub-windings included in the first to Nth sub-insulating transformers are identical, and the N first sub-windings are connected in series between the first and second main terminals to configure the first main winding, and
the polarity directions of the N second sub-windings included in the first to Nth sub-insulating transformers are identical, and the N second sub-windings are connected in series between the third and fourth main terminals to configure the second main winding.