Engineering Case
Oil-Immersed Transformers: Safe, Durable, and Environmentally Friendly
Release time:
2026-03-31 14:09
Oil-immersed transformers are essential electrical components widely utilized in power generation, transmission, distribution, and industrial power systems. By using insulating oil as both a cooling and dielectric medium, these transformers achieve high operational efficiency and an extended service life. This article provides a comprehensive overview of their working principles, key features, and typical applications to help you better understand this critical power equipment.
Working Principle
Oil-immersed transformers operate based on the principle of electromagnetic induction. When an AC voltage is applied to the primary winding, it generates an alternating magnetic flux within the iron core. This flux couples to the secondary winding through the core, inducing the corresponding output voltage.During current flow, heat is generated due to resistive and hysteresis losses. The cooling process is managed as follows:
- Heat Transfer: Heat is conducted from the windings and core to the surrounding transformer oil.
- Convection: The heated oil decreases in density and rises, flowing toward the radiators.
- Cooling: As the oil passes through the radiator surfaces, it is cooled by ambient air and subsequently sinks back to the bottom of the tank.
- Continuous Circulation: This persistent oil circulation ensures the transformer remains within safe temperature limits even under rated loads.
Technical Specifications
Our oil-immersed transformers cover a broad range of application requirements with the following primary specifications:
- Rated Capacity: 30kVA – 2500kVA (Customizable based on actual load requirements)
- Voltage Levels: 6kV, 10kV, 35kV, etc.
- Frequency: 50Hz / 60Hz
- Compliance Standards: IEC 60076, GB 1094, GB 10228, etc.
These parameters ensure our transformers meet the diverse demands of urban distribution, industrial power, and renewable energy systems.
Key Features
- Superior Insulation and Safety: Utilizing specialized insulating oil with a high flash point and high dielectric strength, our transformers effectively prevent internal short circuits and breakdowns, enhancing grid safety.
- Hermetically Sealed for Longevity: The fully sealed tank structure isolates the oil from air and moisture. This prevents oil oxidation and significantly extends maintenance cycles.
- Low Loss and Eco-Friendly: Optimized core materials (high-permeability silicon steel sheets) reduce no-load losses, lowering long-term operational costs.
- High Environmental Adaptability: Whether in high-altitude, high-humidity, or industrial sites with severe load fluctuations, the equipment maintains stable power output.
Typical Applications
Our oil-immersed transformers are widely deployed across several critical sectors:
- Urban Power Grids: Substations and distribution networks.
- Industrial Parks: High energy-consuming industries such as steel mills and chemical plants.
- Renewable Energy: Step-up stations for wind farms and photovoltaic (solar) power plants.
- Infrastructure: Power supply for railways, tunnels, and large-scale bridges.
Selection Guide
When consulting with our engineers, we recommend focusing on the following dimensions:
- Rated Capacity: Select the appropriate capacity based on your total load demand.
- Voltage Class: Ensure the rated voltage matches your local grid specifications.
- Installation Environment: For corrosive or coastal environments, custom reinforced anti-corrosion coatings are available.
- Cooling Method: Choose between ONAN (Oil Natural Air Natural) or ONAF (Oil Natural Air Forced) based on site conditions.
Conclusion
Nanjing Zhengrui Electric Power Technology Co., Ltd. specializes in the R&D of high-reliability power equipment. Our transformers feature high cooling efficiency, superior insulation, and long-term durability, with a proven track record in international markets. Whether for urban distribution, industrial power, or renewable energy projects, our oil-immersed transformers are the key to ensuring safe and stable power.
If you are looking for an efficient and durable power solution, please contact our expert team for a detailed quotation.
Related News
On November 28, 2023, a much-anticipated event-the inaugural meeting of the Lishui District Women's Enterprise Association was held in Nanjing John Garden Hotel. Female entrepreneurs from all over the district gathered together to witness this historic moment.
On March 30, 2023, the leaders of Xuzhou Branch of South-to-North Water Diversion Group East Line Co., Ltd. visited our company for investigation and inspection, accompanied by Executive Deputy General Manager Tang Xiaofeng and Party Secretary Liang Jiguang.
Xu Tongcun Enters Nanjing Zhengrui with His Novel Time
Shakespeare said: "books are the best nutrition in the world." Du Fu also wrote a famous sentence through the ages: "Reading breaks through thousands of books, and writing is like a god." Gorky also has his own view: "the book is the ladder of human progress." Today, Mr. Xu Tongcun brought "Time" into Zhengrui and held a reading sharing meeting.
Contact Us
Address: No.26, Tuanshan East Road, Economic Development Zone, Lishui District, Nanjing City, Jiangsu Province
Link
