66 69kV power transformer uses high-performance silicon steel sheets and a fully sealed structure design, with excellent insulation performance and thermal stability. The product complies with international and national standards, such as 1 . IEC 60076 Power Transformers; 2. AS NZS 60076 Power Transformers CSAC88-16 Power Transformers 3.ANSI/IEEE C57.12.00 IEEE Standard for General Requirements for Liquid-Immersed Distribution, Power, and Regulating Transformers; 4. GOST R 52719 Power Transformers - General Specifications; 5. EN60076 Poer Transformer;8. Local After-Sales Services In North America South Efficiency typically exceeds 99.2–99.4% at full load, with low sound levels and robust corrosion protection for reliable long-term operation.
The 66kV / 69kV Power Transformer is a high-voltage transformer designed for power transmission, utility substations, industrial power systems, and renewable energy applications. It provides reliable voltage conversion between high-voltage networks and medium-voltage distribution systems, ensuring stable, efficient, and continuous power supply for large-scale electrical projects.
Designed for demanding power grid environments, the transformer combines advanced electromagnetic design, high-quality materials, and precision manufacturing technology to achieve excellent efficiency, strong mechanical performance, and long-term operational reliability.
The transformer adopts a high-quality grain-oriented silicon steel core with a multi-step lap joint structure to optimize magnetic flux distribution.
The advanced core design provides:
The optimized magnetic circuit minimizes eddy current losses and improves overall transformer performance.
The 66kV / 69kV Power Transformer uses high-conductivity copper or aluminum windings manufactured with advanced winding technology.
The winding structure is designed to provide:
The winding configuration can be customized according to project requirements, including voltage ratio, capacity, and operating conditions.
The transformer adopts a high-quality oil-paper insulation system, using transformer oil as both an insulation medium and cooling medium.
The insulation system provides:
The transformer can be equipped with advanced insulation monitoring and protection systems to improve operational safety.
The transformer is equipped with an efficient oil cooling system to maintain stable operating temperatures during continuous operation.
Available cooling methods:
The cooling system ensures reliable performance under different environmental conditions.
The transformer tank is manufactured using high-strength steel with advanced welding and sealing technology.
Features include:
Optional accessories include:
Each 66kV / 69kV Power Transformer is produced under strict quality control procedures.
1. Core Manufacturing
2. Winding Production
3. Assembly & Drying
4. Final Testing
Complete factory testing includes:
✔ No-load loss test
✔ Load loss test
✔ Voltage ratio test
✔ Winding resistance test
✔ Insulation resistance test
✔ Dielectric strength test
✔ Temperature rise test
✔ Leakage test
✔ Protection function test
Suitable for:
Available options:
Zisheng are a professional 19+ years manufacturer in producing Oil-Immersed Transformers, Compact Substation, Pad Mounted Transformers, Pole Mounted Transformers and Dry Type Transformers. We own the certificates of ISO/CE/IEC 60076 and TUV Rheinland.
Transformers undergo rigorous FAT and type testing, support voltage/capacity customization. Welcome to consult for Catalog and Product. you can contact us at email [email protected].
A large industrial park required a reliable high-voltage power supply system to support multiple factories, production equipment, and supporting facilities. Due to the increasing electricity demand and the need for stable long-term operation, the customer selected a 66kV Power Transformer for the main substation.
The transformer was designed with a low-loss silicon steel core, high-strength copper winding structure, efficient ONAN cooling system, and advanced protection accessories to ensure stable voltage conversion and reliable operation under continuous heavy loads.
During installation and commissioning, the transformer successfully passed all electrical performance tests and was integrated into the industrial park power network. It now provides a stable power supply for industrial production and improves the overall reliability of the regional distribution system.
Project Type: Industrial Park Substation
Product: 66kV Power Transformer
Application: High Voltage Power Distribution
Voltage Ratio: 66kV / 11kV (Customized)
Cooling Method: ONAN / ONAF
Standard: IEC 60076
66kV / 69kV Power Transformer — Reliable High Voltage Solution Supporting Industrial Development and Modern Power Infrastructure.
| Rated Power | 5000-400000kVA |
| Rating Primary Voltage | 69kV 66kV 63kV or others |
| Secondary Voltage | 33kV 13.8kV 11kV Customized |
| Frequency | 50/60Hz |
| Vector Group | Dyn11, YNd1, Dyn1, YNd11 or others |
| Winding Material | Aluminum/Copper |
| Efficiency | As IEEE, CAS Std or Customized |
| Impedance Voltage | As IEC |
| Altitude | ≤1,000m or Customized |
| Enclosure material | Mid Steel |
| HV Bushing |
| LV Bushing |
| OLTC/NLTC |
| Lifting hook for complete transformer |
| Name plate |
| Oil temperature |
| Winding temperature |
| Radiators |
| Oil level |
| Pressure relief valve |
| CT |
The 66kV / 69kV Power Transformer is widely used in high-voltage transmission and distribution systems, providing reliable voltage conversion and stable power supply for large-scale energy and industrial projects.
Used in transmission substations and regional distribution networks to step down high voltage electricity and deliver stable power to residential, commercial, and industrial users.
Typical applications:
Applied in solar power plants, wind farms, and energy storage systems for collecting generated power and connecting renewable energy sources to the grid.
Typical applications:
Provides reliable power supply for large industrial loads and continuous production operations.
Typical industries:
Designed to support heavy-duty electrical systems in remote mining areas.
Applications include:
Provides stable electricity for energy infrastructure with high reliability requirements.
Applications include:
Used in large public and transportation infrastructure requiring continuous power supply.
Applications include:
Used for voltage transformation and power transmission from generation sources to the electrical grid.
Typical applications:
The 66kV / 69kV Power Transformer is mainly used in high-voltage transmission and distribution systems, including utility substations, industrial parks, renewable energy projects, mining operations, and large infrastructure facilities.
It provides high efficiency, reliable voltage conversion, strong overload capability, excellent short-circuit resistance, and long service life, making it suitable for continuous operation in large-scale power systems.
The voltage ratio can be customized according to project requirements, such as:
Other voltage configurations are available based on customer requirements.
Common cooling methods include:
The cooling system can be customized according to capacity and operating conditions.
Yes. The transformer can be designed for demanding environments, including:
Additional protection such as corrosion-resistant coating and enhanced sealing can be provided.
The transformer can be equipped with various protection and monitoring accessories:
Each transformer undergoes complete factory testing, including:
✔ No-load loss test
✔ Load loss test
✔ Voltage ratio test
✔ Winding resistance test
✔ Insulation resistance test
✔ Dielectric strength test
✔ Temperature rise test
✔ Leakage test
Yes. Customized solutions are available for:
The transformer is manufactured according to international standards such as IEC 60076, ensuring reliable performance, safety, and quality.
With proper installation, operation, and regular maintenance, the transformer can provide reliable service for 25–30 years or longer.
Project— Customized Low-Voltage Distribution Equipment Case Study for a Coastal Industrial Project in South America Guayaquil, the largest city in Ecuador, is...
Technical GuidanceIn industrial power distribution, building power supply, and new energy projects, dry-type transformers are widely used in indoor substations, data centers, rail...
Technical GuidanceIn modern power systems, transformers play a vital role in voltage transformation, power transmission, and load distribution. From stepping up voltage for...
