2026 Best 10 oil immersed transformer Factory in the world

Introduction to Oil Immersed Transformer

Oil - immersed transformers are a type of power transformer that use insulating oil as both a coolant and an insulating medium. The insulating oil provides excellent electrical insulation properties, which helps prevent electrical breakdown between the windings and other components of the transformer. It also has good heat - transfer capabilities, allowing it to carry away the heat generated during the operation of the transformer, thus ensuring the normal and stable operation of the transformer. These transformers are widely used in power systems, industrial and commercial facilities, and other fields due to their high reliability, long service life, and relatively low cost.

Top 10 Oil Immersed Transformer Factories

1. Zhejiang Rsafele Electric Co., Ltd.

Zhejiang Rsafele Electric Co., Ltd. is a leading enterprise in the field of power equipment manufacturing. With years of experience and a strong R & D team, the company is committed to providing high - quality oil - immersed transformers.

The company adheres to strict quality control standards throughout the production process. From the selection of raw materials to the final assembly and testing, every step is carefully monitored. The raw materials used in their oil - immersed transformers, such as high - quality silicon steel sheets and insulating oil, are sourced from reliable suppliers. This ensures the high performance and long - term stability of the transformers.

In terms of technology, Zhejiang Rsafele Electric Co., Ltd. continuously invests in research and development. They have developed advanced manufacturing processes that can improve the efficiency and reduce the energy loss of oil - immersed transformers. For example, their unique winding technology can optimize the magnetic field distribution in the transformer, thereby reducing eddy current losses.

The company also provides excellent after - sales service. They have a professional after - sales team that can quickly respond to customers' needs, provide on - site maintenance and technical support. This has won the trust and praise of many customers at home and abroad.

Website: https://www.rsafepower.com/

2. ABB Group

ABB is a global leader in power and automation technologies. With a history spanning over a century, ABB has a wealth of experience in the design and manufacture of oil - immersed transformers.

ABB's oil - immersed transformers are known for their high - end technology and reliability. They use advanced materials and manufacturing processes to ensure the performance of the transformers. For example, ABB's transformers are equipped with state - of - the - art cooling systems, which can effectively dissipate heat and maintain the stable operation of the transformer even under high - load conditions.

The company has a global R & D and production network. Their R & D centers are constantly exploring new technologies and materials to improve the efficiency and environmental friendliness of oil - immersed transformers. In addition, ABB's strict quality control system ensures that every transformer leaving the factory meets the highest international standards.

ABB also provides comprehensive solutions for power systems. They can customize oil - immersed transformers according to the specific needs of different customers, whether it is for large - scale power grids or industrial plants.

3. Siemens AG

Siemens is a well - known German multinational company with a strong presence in the energy and industrial sectors. In the field of oil - immersed transformers, Siemens has a long - standing reputation.

Siemens' oil - immersed transformers are characterized by their high - precision design and excellent performance. They use advanced simulation and modeling techniques in the design process to optimize the structure and performance of the transformers. This results in transformers with low losses, high efficiency, and long service life.

The company has a strict quality management system. From the procurement of raw materials to the final product delivery, every link is strictly controlled. Siemens also invests heavily in research and development to keep up with the latest technological trends. For example, they are exploring the use of new insulating materials to improve the insulation performance and safety of oil - immersed transformers.

Siemens has a global service network. They can provide timely technical support and maintenance services to customers around the world, ensuring the continuous and reliable operation of their transformers.

4. Schneider Electric

Schneider Electric is a global specialist in energy management and automation. Their oil - immersed transformers are designed to meet the diverse needs of different industries.

Schneider Electric focuses on innovation in its transformer products. They use advanced digital technologies to monitor and control the operation of oil - immersed transformers. For example, their transformers can be equipped with sensors that can collect real - time data on temperature, voltage, and current, allowing for remote monitoring and predictive maintenance.

The company's oil - immersed transformers are also known for their high - quality construction. They use high - grade materials and advanced manufacturing processes to ensure the durability and reliability of the transformers. Schneider Electric also emphasizes environmental protection in its product design. Their transformers are designed to be energy - efficient, reducing energy consumption and environmental impact.

In addition, Schneider Electric provides comprehensive training and support services to its customers. They can help customers install, operate, and maintain their oil - immersed transformers, ensuring that customers can get the most out of their products.

5. Toshiba Corporation

Toshiba is a Japanese multinational conglomerate with a long history in the electrical and electronics industry. In the field of oil - immersed transformers, Toshiba has a strong technical strength.

Toshiba's oil - immersed transformers are characterized by their high - performance and advanced technology. They use advanced insulation materials and cooling systems to improve the efficiency and reliability of the transformers. For example, Toshiba's transformers are equipped with a unique oil - circulation system that can effectively dissipate heat and ensure the stable operation of the transformer.

The company has a strict quality control system. They conduct rigorous testing on every transformer before it leaves the factory, including electrical performance testing, insulation testing, and temperature rise testing. This ensures that the transformers meet the highest quality standards.

Toshiba also has a strong R & D team. They are constantly exploring new technologies and materials to improve the performance and environmental friendliness of their oil - immersed transformers. For example, they are researching the use of biodegradable insulating oil to reduce the environmental impact of the transformers.

6. Hitachi, Ltd.

Hitachi is a well - known Japanese company with a wide range of business in the energy, industrial, and information technology sectors. In the field of oil - immersed transformers, Hitachi has a high - level of technology and manufacturing capabilities.

Hitachi's oil - immersed transformers are designed with high - precision and advanced technology. They use advanced magnetic materials and winding techniques to reduce losses and improve efficiency. For example, Hitachi's transformers can achieve a very low no - load loss, which is beneficial for energy conservation.

The company has a strict quality management system. They pay attention to every detail in the production process, from the selection of raw materials to the final assembly. Hitachi also conducts comprehensive testing on its transformers to ensure their performance and reliability.

Hitachi is also committed to innovation. They are constantly developing new technologies and products to meet the changing needs of the market. For example, they are exploring the use of smart grid technologies in their oil - immersed transformers to improve the integration of the transformers into the power grid.

7. Mitsubishi Electric Corporation

Mitsubishi Electric is a leading Japanese company in the electrical and electronics field. Their oil - immersed transformers are known for their high - quality and advanced technology.

Mitsubishi Electric uses advanced manufacturing processes and materials in the production of oil - immersed transformers. They have a unique design concept that focuses on improving the performance and reliability of the transformers. For example, their transformers are designed with a compact structure, which can save space and reduce installation costs.

The company has a strict quality control system. They conduct multiple inspections and tests during the production process to ensure that the transformers meet the highest quality standards. Mitsubishi Electric also provides excellent after - sales service. They have a professional service team that can provide timely maintenance and technical support to customers.

In addition, Mitsubishi Electric is actively involved in research and development. They are exploring new technologies such as superconducting materials and advanced insulation technologies to further improve the performance of their oil - immersed transformers.

8. General Electric (GE)

General Electric is an American multinational conglomerate with a long - standing history in the energy and industrial sectors. In the field of oil - immersed transformers, GE has a strong technical and manufacturing base.

GE's oil - immersed transformers are characterized by their high - performance and reliability. They use advanced materials and manufacturing processes to ensure the quality of the transformers. For example, GE's transformers are equipped with advanced protection systems that can detect and prevent potential faults, ensuring the safe operation of the transformers.

The company has a global R & D and production network. They are constantly innovating and improving their products. GE also provides comprehensive solutions for power systems, including the design, installation, and maintenance of oil - immersed transformers.

GE is also committed to environmental protection. They are developing more energy - efficient and environmentally friendly oil - immersed transformers to reduce the environmental impact of the power industry.

9. Hyosung Heavy Industries

Hyosung Heavy Industries is a South Korean company with a strong presence in the power equipment manufacturing industry. Their oil - immersed transformers are popular in the Asian market.

Hyosung Heavy Industries focuses on the quality and performance of its oil - immersed transformers. They use high - quality materials and advanced manufacturing processes to ensure the reliability and durability of the transformers. For example, their transformers are designed with a high - strength structure that can withstand harsh environmental conditions.

The company has a strict quality control system. They conduct comprehensive testing on every transformer before it leaves the factory, including electrical performance testing, mechanical performance testing, and insulation testing. Hyosung Heavy Industries also provides excellent after - sales service. They have a professional service team that can provide on - site maintenance and technical support to customers.

In addition, Hyosung Heavy Industries is constantly investing in research and development. They are exploring new technologies and materials to improve the performance and efficiency of their oil - immersed transformers.

10. Bharat Heavy Electricals Limited (BHEL)

BHEL is an Indian public - sector undertaking and a leading manufacturer of power equipment in India. Their oil - immersed transformers are widely used in the Indian power grid.

BHEL's oil - immersed transformers are known for their high - quality and cost - effectiveness. They use locally sourced materials and advanced manufacturing processes to produce transformers that meet the specific needs of the Indian market. For example, their transformers are designed to operate in a wide range of environmental conditions, including high - temperature and high - humidity areas.

The company has a strict quality control system. They conduct rigorous testing on every transformer to ensure its performance and reliability. BHEL also provides comprehensive after - sales service, including installation, commissioning, and maintenance.

BHEL is also involved in research and development. They are working on improving the efficiency and environmental friendliness of their oil - immersed transformers, and are exploring new technologies to meet the future needs of the power industry.

Summary

The above - mentioned 10 companies are among the best oil - immersed transformer factories in the world in 2026. Each company has its own unique advantages, whether it is in terms of technology, quality control, after - sales service, or innovation. Zhejiang Rsafele Electric Co., Ltd. stands out with its high - quality products and excellent after - sales service, while global giants like ABB, Siemens, and Schneider Electric bring advanced technologies and comprehensive solutions to the table. Japanese companies such as Toshiba, Hitachi, and Mitsubishi Electric are known for their high - precision manufacturing and continuous innovation. American company GE and South Korean company Hyosung Heavy Industries also have strong capabilities in the field of oil - immersed transformers. Indian company BHEL provides cost - effective solutions for the local market. These companies together drive the development of the oil - immersed transformer industry, and will continue to play an important role in the future power system.