Home/Products/Power Transformers

Oil-Immersed
Power Transformers.

34.5 kV through 765 kV, ratings up to 800 MVA — designed to IEEE C57 for the US grid. Delivered in 5 to 10 months, against current OEM backlogs of 18 to 36.

CaptionStep-up generator transformer under final assembly — 500 kV class, ONAF cooling.
Asset refPT-525-500-UA-024
Voltage Class Up to 765 kV 34.5 / 115 / 230 / 345 / 500 / 765 kV grid
Power Rating Up to 800 MVA Three-phase or single-phase units
Lead Time 5 – 10 mo vs. 18 – 36 mo OEM backlog
Standards IEEE C57 .12.00 · .12.10 · ANSI · NEMA TR1
01 · Overview/ what we build

Six transformer families,
one production line.

Step-up GSU, step-down station, autotransformers, phase-shifters, EAF, traction — manufactured at Baku Industrial Complex and the new ATEF-Ukraine facility in Hust.

Family · 01

Step-up GSU

Generator step-up transformers for thermal, hydro, and renewables — typically 230 to 500 kV.

Family · 02

Step-down station

Transmission-to-distribution station transformers for utility and large industrial substations.

Family · 03

Autotransformers

Interconnecting transmission autotransformers — 345/230 kV, 500/345 kV, 765/500 kV ties.

Family · 04

Phase-shifting

Phase-shifting transformers for power flow control on heavily loaded transmission paths.

Family · 05

Electric arc furnace

EAF transformers for steel production — high-current, high-duty, harmonic-tolerant designs.

Family · 06

Traction

Traction transformers for rail electrification and high-speed transit feeder substations.

02 · Capacity/ voltage class · units / year

Annual production,
by voltage class.

Combined Baku + ATEF-Ukraine capacity at full ramp-up. Higher kV classes consume more factory time per unit — the volume mix shifts toward distribution at lower classes.

Voltage classAnnual capacityLead time
765kV
up to 8 units
7 – 10 mo
500kV
up to 12 units
7 – 10 mo
345kV
up to 26 units
5 – 8 mo
115kV
up to 50 units
5 – 6 mo
34.5kV
up to 100 units
4 – 5 mo
03 · Manufacturing inputs/ what's behind the spec

Core to test bay,
under one roof.

GEORG core lines, vertical winding machines, vapor-phase drying, HighVolt + OMICRON test bay with Faraday-cage shielded room — operations competitors typically distribute across external suppliers.

Step · 0101

Core processing

  • GEORG + SAGMA automatic core cutting lines
  • STEP-LAP construction, grain-oriented steel from 0.18 mm
  • Hydraulic-adjustable assembly tables, banding machines
Step · 0202

Winding

  • Vertical and horizontal winding machines
  • Single coil capacity up to 30 tons
  • CTC support for low-loss high-current designs
Step · 0303

Active part

  • Vapor-phase drying in solvent vapor environment
  • Active part assembly under controlled humidity
  • Combined drying and pressing furnaces, vacuum extraction
Step · 0404

Testing center

  • HighVolt HV test sets, OMICRON measurement
  • Faraday-cage shielded room, PD ≤5 pC
  • Oil and insulation chemical analysis lab
04 · Lead time/ atef vs us oem backlog

2 – 3× faster
than US OEM backlog.

Major US OEMs currently quote 18 to 36 months for new orders. ATEF Group's manufacturing capacity is available now — production slots open across all voltage classes.

ATEF Energy US OEM backlog (typical)
Scale0 mo36 mo
115 – 230 kV
ATEF
5 – 6 mo
OEM
18 – 24 mo
345 – 500 kV
ATEF
7 – 9 mo
OEM
24 – 30 mo
765 kV
ATEF
8 – 10 mo
OEM
30 – 36 mo
05 · Standards & testing/ certifications · type tests

Designed to IEEE C57.
Tested by KEMA and CESI.

Third-party type-test reports on existing serial production from KEMA (Netherlands) and CESI (Italy). Project-specific IEEE C57.12.90 reports issued under each US contract.

A · Designed toFive standards families
IEEE C57.12.00General requirements for liquid-immersed distribution and power transformers
IEEE C57.12.10Liquid-immersed power transformers ≥501 kVA, 230 kV and below
ANSIUS grid compatibility, terminal markings, nameplate practice
NEMA TR1US-market dimensional and performance practice
IEC 60076International equivalent — for export and dual-spec projects
B · Tested byIndependent labs
KEMANetherlands

IEC 60076 type-test reports on serial production.

CESIItaly

Short-circuit and dielectric type tests.

Project-specific IEEE C57.12.90 type-test reports issued under each US contract.
C · CertifiedQuality management
ISO 9001Quality
ISO 14001Environment
ISO 45001Safety
06 · Related/ same manufacturing line

From the same line.

Reactors and substation equipment are built on the same factory floor, by the same engineering team, under the same quality system.

07 · Request a quote

Have an SLD
or a load list?

Send specifications, a single-line diagram, or a draft RFQ. Our US-based engineering team confirms voltage class, sizing, and lead time within one business day.

Voltage34.5 – 765 kV
RatingUp to 800 MVA
Response< 1 business day