Energy
18 columns
100 rows
8 formats

Power Transformers and Autotransformers

This dataset provides detailed technical and operational specifications for power transformers and autotransformers, including electrical ratings, impedance, tap changer settings, winding configurations, and cooling methods. It is designed for asset management, grid modeling, and operational optimization in electric power systems, supporting both engineering analysis and maintenance planning.

last updated 2 Nov 2025
by GoMask

The brief that made it

Power grid asset management and inventory tracking

Sample rows

preview · 8 of 100 rows · all 18 columns

transformer_idstring	cooling_typestring	mva_ratingfloat	manufacturerstring	transformer_typestring	primary_voltage_kvfloat	secondary_voltage_kvfloat	impedance_percentfloat	tap_ratio_minfloat	tap_ratio_maxfloat	tap_step_percentfloat	number_of_tap_positionsinteger	load_tap_changer_presentboolean	winding_configurationstring	installation_locationstring	year_of_manufactureinteger	serial_numberstring	in_serviceboolean
TX-001-PTA	ONAN	50	ABB	Power Transformer	220	110	10.4	0.95	1.05	1.25	17	true	Delta-Wye	Central Substation	2014	ABB-PT-2014-00945	true
TX-002-ATB	ONAF	80.5	Siemens	Autotransformer	400	220	7.8	0.98	1.06	1.5	15	true	Wye-Wye	South Grid Hub	2018	SIE-AT-18-2578	true
TX-003-PTC	OFAF	25.2	GE	Power Transformer	110	33	8.3	0.97	1.03	1	9	true	Delta-Delta	East Transmission Site	2012	GE-PT-12-0427	true
TX-004-PTD	ONAN	16	Hitachi	Power Transformer	33	11	5.5	0.99	1.01	0.5	5	true	Wye-Delta	North Distribution	2019	HIT-PT-19-2345	true
TX-005-PTA	OFWF	100	Hyundai	Power Transformer	500	230	9.2	0.94	1.06	1.2	13	true	Wye-Wye	West Main Substation	2007	HYU-PT-07-8173	true
TX-006-PTB	ONAF	40.5	Toshiba	Power Transformer	66	11	6.8	0.98	1.04	1	7	true	Delta-Wye	Metro Distribution	2015	TOS-PT-15-3342	true
TX-007-ATC	ONAF	60	Alstom	Autotransformer	220	132	5.2	0.96	1.03	0.75	11	true	Wye-Wye	Grid Junction A	2020	ALS-AT-20-6543	true
TX-008-PTD	ONAN	12.5	Siemens	Power Transformer	33	6.6	7	0.99	1.01	0.5	3	true	Delta-Delta	Rural East	2016	SIE-PT-16-0998	true
TX-009-PTA	OFAF	125	GE	Power Transformer	500	230	8.7	0.93	1.05	1.4	12	true	Delta-Wye	West Regional Hub	2011	GE-PT-11-3071	true
TX-010-PTB	ONAN	10.2	Hitachi	Power Transformer	33	6.6	6.5	0.98	1.02	0.5	5	true	Wye-Delta	Village Center	2017	HIT-PT-17-7812	true
TX-011-ATD	ONAF	70	ABB	Autotransformer	330	220	13.2	0.95	1.07	2	13	true	Wye-Wye	Central Station	2015	ABB-AT-15-3322	true
TX-012-PTC	ONAN	20	Toshiba	Power Transformer	66	11	6.3	0.97	1.03	1	7	true	Delta-Wye	City East Substation	2013	TOS-PT-13-1282	true
TX-013-PTD	ONAN	6.3	GE	Power Transformer	33	6.6	5.9	0.99	1.01	0.5	3	true	Delta-Delta	Remote Substation	2016	GE-PT-16-4398	true
TX-014-PTA	ONAF	55	Hyundai	Power Transformer	220	110	10.1	0.95	1.05	1.2	13	true	Delta-Wye	Urban Center	2009	HYU-PT-09-1609	true
TX-015-PTB	OFAF	18.5	Hitachi	Power Transformer	66	11	6	0.97	1.03	1	7	true	Wye-Delta	Industrial Park	2014	HIT-PT-14-2382	true
TX-016-PTC	ONAN	35	ABB	Power Transformer	110	33	8.1	0.96	1.04	1	9	true	Delta-Wye	Suburban Substation	2010	ABB-PT-10-1092	true
TX-017-PTD	ONAN	13.7	GE	Power Transformer	33	6.6	7.5	0.99	1.01	0.5	5	true	Delta-Delta	Rural West	2018	GE-PT-18-5987	true
TX-018-PTA	ONAF	45	Hyundai	Power Transformer	220	110	10	0.95	1.05	1.25	17	true	Delta-Wye	Downtown Grid	2005	HYU-PT-05-6283	true
TX-019-PTB	OFAF	20	Toshiba	Power Transformer	66	11	6.3	0.97	1.03	1	7	true	Delta-Wye	City West Substation	2012	TOS-PT-12-2382	true
TX-020-ATC	OFWF	120	Siemens	Autotransformer	400	220	7.9	0.97	1.06	1.4	12	true	Wye-Wye	Interstate Junction	2017	SIE-AT-17-7432	true

What the 100 rows show

from the 100-row sample

OFWF (cooling type) stands out: mean mva_rating is 191.4, against 45.7 for the rest.

39.0median mva_rating
2transformer types
4winding configurations
110.0median primary_voltage_kv
13.8median secondary_voltage_kv
7.5median impedance_percent

Mean mva_rating by cooling_type100 rows

mva_rating100 rows, in bands of 50

Median 39.0, from 6.3 to 300.0.

manufacturer100 rows · top 10 of 15 values

ABB14
GE12
Hitachi10
Siemens8
Hyundai6
Toshiba6
Siemens Energy6
GE Grid Solutions6
Hyundai Electric6
Hitachi Energy6

18 columns by typefrom the column list below

string 7
integer 2
float 7
boolean 2

Columns

18 columns in three groups

blueprint · 18 columns
column	type	description	example
Text 7 columns
`transformer_id`	string	Unique identifier for each transformer or autotransformer unitunique	TX-001-PTA
`transformer_type`	string	Type of transformer (e.g., Power Transformer, Autotransformer)Power Transformer · Autotransformer	Power Transformer
`winding_configuration`	string	Winding configuration (e.g., Delta-Wye, Wye-Wye, Delta-Delta)Delta-Wye · Wye-Wye · Delta-Delta · Wye-Delta · Other	Delta-Wye
`cooling_type`	string	Cooling method used (e.g., ONAN, ONAF, OFAF, OFWF)ONAN · ONAF · OFAF · OFWF · Other	ONAN
`installation_location`	string	Physical location or substation where the transformer is installedoptional	Central Substation
`manufacturer`	string	Name of the transformer manufactureroptional	ABB
`serial_number`	string	Manufacturer's serial number for the transformeroptional	ABB-PT-2014-00945
Numbers 9 columns
`mva_rating`	float	Apparent power rating of the transformer in MVA0.1 or more	50
`primary_voltage_kv`	float	Rated primary winding voltage in kilovolts (kV)0.1 or more	220
`secondary_voltage_kv`	float	Rated secondary winding voltage in kilovolts (kV)0.1 or more	110
`impedance_percent`	float	Transformer impedance expressed as a percentage0.01 to 100	10.4
`tap_ratio_min`	float	Minimum tap ratio available for voltage adjustment0.5 or more	0.95
`tap_ratio_max`	float	Maximum tap ratio available for voltage adjustment0.5 or more	1.05
`tap_step_percent`	float	Percentage change per tap step0.01 to 10	1.25
`number_of_tap_positions`	integer	Total number of tap positions available1 or more	17
`year_of_manufacture`	integer	Year the transformer was manufactured1,900 to 2,100 · optional	2014
True or false 2 columns
`load_tap_changer_present`	boolean	Indicates if a load tap changer is installed	true
`in_service`	boolean	Indicates whether the transformer is currently in service	true

Use it for

An energy dashboard
Mva_rating by cooling_type and a breakdown of manufacturer. Excel, Power BI or Tableau.
Why do the 14 OFWF rows have a mean mva_rating of 191.4?
A root-cause class exercise
Hand out the rows and one question. The answer is in the data, not in the brief.
Transformers100
TX-001-PTA50ONAN
TX-002-ATB80.5ONAF
TX-003-PTC25.2OFAF
A software demo
Believable transformers with transformer_type, mva_rating and primary_voltage_kv to fill a screen in front of a buyer.

This dataset100 rows18 columns

Yours1,000 rows18 columnsinstallation_location: UK only

blueprint · power-transformers-and-autotransformers

Behind this dataset

Same schema. As many rows as you need.

These 100 rows came out of a blueprint — 18 columns with generation rules behind each one. Open it in Data Factory to retune a column, add your own, wire in foreign keys, and run it at the size you actually need.

Rules it was built with

Transformer ID unique per unit
MVA rating: base, forced air (FOA), forced oil (FOW)
Voltage ratio: primary/secondary (e.g., 230/115 kV)
Winding connection: wye, delta, zigzag
Impedance on transformer base (% or per unit)
Tap changer type: no-load (NLTC), on-load (OLTC/LTC)
Tap range: typically ±10% in 32 steps (5/8% per step)
Load tap changer (LTC) control mode: manual, automatic, voltage control

Rows1,000 rows10,000 rows100,000 rows1,000,000 rows

Open the blueprint in Data Factory

1 credit per row. Preview 20 rows free. Buy rows for the full run.

Exports: CSV, JSON, JSONL, Parquet, SQL, Excel, TSV, XML
Licence: yours to use, including commercially
API slug: power-transformers-and-autotransformers

What should your data show?

No signup. No card.

Sample rows

What the 100 rows show

Columns

Use it for

An energy dashboard

A root-cause class exercise

A software demo

Make it yours.

Same schema. As many rows as you need.

More in Energy

What should your data show?