IP Library › Granted Patent US 12,347,599
Granted Patent B2
US 12,347,599 · App. 18/715,106 · Granted Jul 1, 2025

Transformer system for a direct current converter system

Inventors: Erik Carl Wedin (Karlstad, SE); Semen Pyrog (Isernhagen, DE); Erik Lysell (Ludvika, SE)
Assignee: HITACHI ENERGY LTD
H01F27/28H02M7/003
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,347,599
App. No.
18/715,106
Granted
Jul 1, 2025
Kind
B2
Abstract

A transformer system for a direct current converter system includes a plurality of windings for three electrical phases, the windings being electrically connected to provide a 15° phase shift, and including at least three separate tanks, wherein the associated to different electrical phases are located in different ones of the separate tanks.

Claims (15)

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.

2. The transformer system according to claim 1 , wherein the first winding and the second winding for the same electrical phase are located on separate limbs of the common core.

3. The transformer system according to claim 1 , wherein the first winding and the second winding for the same electrical phase are electrically connected to each other within the same tank.

4. The transformer system according to claim 1 , wherein a ratio of a number of turns in the first winding and in the second winding for the same electrical phase and/or a ratio of a voltage during operation at the first winding and at the second winding for the same electrical phase is a square root of three.

5. The transformer system according to claim 1 , comprising at least three lead-through connections for one of the transformer sides for each electrical phase.

6. The transformer system according to claim 5 , comprising exactly three and not more lead-through connections for one of the transformer sides for each electrical phase.

7. A direct current converter system comprising the transformer system according to claim 1 and comprising a line commutated converter connected to the plurality of windings of the transformer system.

8. The direct current converter system of claim 7 , comprising two of the transformer systems and comprising two line commutated converters, each line commutated converter being connected to the plurality of windings of one of the transformer systems.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 30, 2024
From: WEDIN, ERIK CARL; PYROG, SEMEN; LYSELL, ERIK
To: HITACHI ENERGY SWITZERLAND AG
Reel/Frame 067575/0174 →
MERGER Recorded May 30, 2024
From: HITACHI ENERGY SWITZERLAND AG
To: HITACHI ENERGY LTD
Reel/Frame 067575/0191 →
Continuity (1)
Related Publication 20240428979A1 · Dec 26, 2024
References Cited (24)
US 3235823A · Renberg, Jr. · 1966 [cited by examiner]
US 20200203066A1 · Schweiger · 2020 [cited by examiner]
CN 106953532A · 2017 [cited by applicant]
CN 209105050U · 2019 [cited by applicant]
CN 112434434A · 2021 [cited by applicant]
CN 216672848U · 2022 [cited by applicant]
DE 102016216949A1 · 2018 [cited by applicant]
EP 0471183A2 · 1992 [cited by applicant]
EP 2587658A2 · 2013 [cited by applicant]
EP 3232452A1 · 2017 [cited by applicant]
EP 3661037A1 · 2020 [cited by applicant]
JP 2000021644A · 2000 [cited by examiner]
International Search Report and Written Opinion of the International Searching Authority, International Application No. PCT/EP2022/070967, mailed Dec. 9, 2022, 9 pages. [cited by applicant]
International Preliminary Report on Patentability, International Application No. PCT/EP2022/070967, mailed Mar. 1, 2024, 7 pages. [cited by applicant]
Written Opinion of the International Preliminary Examining Authority, International Application No. PCT/EP2022/070967, mailed Jul. 21, 2023. [cited by applicant]
Wang, Mengxia et al., “A New 24-pulse Rectifier Transformer with Delta-extended Connection,” IOP Conf. Series: Earth and Environmental Science 223, 2019, 6 pages. [cited by applicant]
Anandpara, Milan et al., “An Active Interphase Transformer for 12-Pulse Rectifier System to Get the Performance Like 24-Pulse Rectifier System,” 10.1109/NPSC.2014.7103802, IEEE, 2014, 6 pages. [cited by applicant]
Mon-Nzongo, D.L. et al., “An Improved Topology for Multi-pulse AC/DC Converters within HVDC and VFD Systems: Operation in Degraded Modes,” IEEE Transactions on Industrial Electronics, vol. 65, No. 5, May 2018, 11 pages. [cited by applicant]
Solak, Krzysztof et al., “Differential Protection of Converter Transformers,” 2016 17th International Scientific Conference on Electric Power Engineering (EPE), Prague, Czech Republic, IEEE, 6 pages. [cited by applicant]
Campostrini, Francesco, Thesis, “Modelling of ‘Extended-Delta’ Transformers for Power Converters,” Universita Degli Studi Di Padova, 2016, 100 pages. [cited by applicant]
Modern Power Systems, “HVDC fifty years on,” published Oct. 31, 2004, downloaded from the Internet on May 28, 2024 from: https://www.modernpowersystems.com/analysis/hvdc-fifty-years-on/, 13 pages. [cited by applicant]
Gaonkar, A.D. et al., “Multi-winding Phase-Shifting Transformer for 36-Pulse Rectifier: Winding Turns Design and Analysis,” 2016 North American Power Symposium (NAPS), Denver, CO, USA, 2016, IEEE, 6 pages. [cited by applicant]
Dortort, Isadore K., Phase Shifting of Harmonics in AC Circuits of Rectifiers, IEEE Transactions on Industry and General Applications, vol. 1GA-4, No. 6, Nov./Dec. 1968, 4 pages. [cited by applicant]
Hitachi, Vindhyachal—Commissioned in 1989, Vindhyachal was the first back-to-back HVDC station in India,: downloaded from the Internet on May 22, 2024 from: https://www.hitachienergy.com/about-us/customer-success-storie… [cited by applicant]