US 12,347,599 B2
Transformer system for a direct current converter system
Erik Carl Wedin, Karlstad (SE); Semen Pyrog, Isernhagen (DE); and Erik Lysell, Ludvika (SE)
Assigned to HITACHI ENERGY LTD, Zürich (CH)
Appl. No. 18/715,106
Filed by Hitachi Energy Ltd, Zürich (CH)
PCT Filed Jul. 26, 2022, PCT No. PCT/EP2022/070967
§ 371(c)(1), (2) Date May 30, 2024,
PCT Pub. No. WO2023/099047, PCT Pub. Date Jun. 8, 2023.
Prior Publication US 2024/0428979 A1, Dec. 26, 2024
Int. Cl. H01F 30/12 (2006.01); H01F 27/28 (2006.01); H02M 7/00 (2006.01)
CPC H01F 27/28 (2013.01) [H02M 7/003 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A transformer system for a direct current converter system,
comprising a plurality of windings for three electrical phases,
the plurality of windings being electrically connected to provide a 15° phase shift,
and comprising at least three separate tanks, wherein the plurality of windings associated to different electrical phases are located in different ones of the separate tanks,
wherein for each electrical phase at least one first winding and at least one second winding electrically connected to each other,
wherein the first winding and the second winding for the same electrical phase are located in the same tank,
wherein the first winding and the second winding for the same electrical phase are located on a common core,
wherein the plurality of windings are connected in an extended-side delta connection, where the first windings in the at least three separate tanks are connected to each other in a delta configuration and the second windings in the at least three separate tanks are extended windings and are connected between the associated first windings and the electrical phases.