Jiangsu Xinhong Electrical Equipment Co., Ltd. , a professional oil immersed transformer manufacturers based in China, has been dedicated to the research, development, and production of high-quality oil immersed transformer products for years. Our three-phase oil-immersed transformers are engineered to meet the stringent demands of global power systems, offering outstanding performance, long service life, and cost-effective operation.
As a leading name among oil immersed transformer China manufacturers, Xinhong Electrical combines advanced manufacturing technology, rigorous quality control, and deep industry expertise to deliver transformers that power progress across the globe.
A three-phase oil-immersed transformer is a static electrical device that transfers electrical energy between circuits through electromagnetic induction, using transformer oil as both an insulating medium and a cooling agent. The core and windings are immersed in a tank filled with high-quality insulating oil, which efficiently dissipates heat generated during operation and provides excellent electrical insulation.
These transformers are typically used in outdoor substations, utility distribution networks, and industrial power systems where reliable, high-capacity voltage transformation is required.
Core: Made of high-permeability cold-rolled grain-oriented silicon steel, minimizing hysteresis and eddy current losses.
Windings: Available in copper or aluminium conductors, wound with precision to ensure uniform flux distribution.
Insulating Oil: High-grade mineral oil or natural ester oil, providing superior dielectric strength and thermal conductivity.
Tank: Robust, fully sealed construction to prevent oil leakage and moisture ingress.
Conservator & Breather: Maintain oil volume and prevent contamination.
Bushings: High-voltage and low-voltage porcelain or composite bushings for safe external connections.
Xinhong Electrical offers a comprehensive range of three-phase oil-immersed transformers to suit diverse applications and capacity requirements.
| Parameter | Range |
|---|---|
| Rated Capacity | 50 kVA – 10,000 kVA |
| Voltage Class | Up to 35 kV |
| Frequency | 50 Hz / 60 Hz |
| Cooling Method | ONAN (Oil Natural Air Natural) |
| Winding Material | Copper / Aluminium (optional) |
| Standard Compliance | IEC 60076, ANSI C57.12, GB/T 6451 |
S11 Series – Energy-efficient distribution transformers
S13 Series – Ultra-low loss, high-efficiency design
S20 Series – Next-generation amorphous alloy core transformers
Custom Designs – Tailored to specific voltage, capacity, and environmental requirements
Xinhong transformers are designed with optimized magnetic circuits and high-quality silicon steel cores, achieving significantly reduced no-load and load losses. Our S13 and S20 series transformers exceed the most stringent energy efficiency standards, helping customers lower operational costs and reduce carbon footprints.
The transformer oil circulates naturally or with forced air assistance, ensuring even heat distribution and preventing hot spots. This allows our transformers to operate reliably even under sustained overload conditions.
Built with heavy-duty tank materials, precision-welded seams, and advanced sealing technology, Xinhong three-phase oil-immersed transformers are resistant to harsh environmental conditions, including high humidity, temperature extremes, and corrosive atmospheres.
With high-grade insulating oil, premium winding materials, and meticulous manufacturing processes, our transformers deliver a design life of over 25 years, minimizing the total cost of ownership.
We offer flexible customization – from capacity and voltage ratings to winding materials, tapping ranges, and accessory configurations – ensuring that each transformer perfectly matches the specific needs of your project.
All Xinhong transformers are designed, tested, and certified in accordance with IEC 60076, ANSI C57.12, and other relevant international standards, ensuring global compatibility and customer confidence.
Our three-phase oil-immersed transformers are trusted by customers across a wide spectrum of industries and sectors:
Utility Power Grids – Distribution and transmission substations
Industrial Facilities – Factories, mines, and manufacturing plants
Commercial Buildings – Shopping malls, office towers, and hotels
Residential Communities – Apartment complexes and housing developments
Renewable Energy – Solar farms, wind power plants, and hydro stations
Infrastructure Projects – Airports, railways, and port facilities
When selecting a transformer for a project, one of the most common decisions is whether to choose an oil immersed transformer vs cast resin transformer (also known as a Dry transformer). Each type has its own strengths, and the choice depends on the specific application environment.
Excellent heat dissipation, suitable for high-capacity and overload conditions
More compact footprint for the same power rating
Longer operational life (typically 25–30 years)
Lower initial cost for large-capacity units
Ideal for outdoor installations
No oil – eliminates fire and environmental risks
Minimal maintenance – no oil testing or filtration
Suitable for indoor installations with strict fire safety requirements
Environmentally friendly – no risk of oil leakage
For outdoor, high-capacity, and high-reliability applications, the oil-immersed transformer remains the preferred choice. For indoor environments with limited ventilation or stringent fire codes, a cast resin transformer may be more appropriate. Xinhong Electrical manufactures both types, and our technical team is ready to assist you in making the optimal selection.
In addition to standalone transformers, Xinhong Electrical offers complete prefabricated substationsolutions. Our compact substations integrate the three-phase oil-immersed transformer with high-voltage and low-voltage switchgear, metering, and protection devices in a single, weatherproof enclosure.
As one of the professional prefabricated substation manufacturers in China, we provide turnkey solutions that significantly reduce installation time, civil works, and on-site commissioning efforts – ideal for urban distribution networks, industrial parks, and temporary power supply projects.
Key benefits of our prefabricated substations include:
Space-saving, modular design
Factory pre-assembled and tested – ready for immediate operation
Customizable to meet specific grid requirements
Suitable for both indoor and outdoor installations
At Jiangsu Xinhong Electrical Equipment Co., Ltd., quality is not just a standard – it is the foundation of our business. Our manufacturing facility is equipped with advanced production lines, including:
Automatic foil winding machines for precise winding
Vacuum drying and oil impregnation systems
High-voltage testing laboratories
Comprehensive quality inspection stations at every production stage
Every transformer undergoes a series of rigorous tests before leaving our factory, including:
Ratio and polarity tests
Winding resistance measurements
No-load loss and load loss tests
Impulse voltage withstand tests
Partial discharge measurements
Oil dielectric strength tests
Our commitment to quality has earned us certifications including ISO 9001, ISO 14001, and OHSAS 18001, reflecting our dedication to quality management, environmental responsibility, and occupational health and safety.
Extensive Experience – Years of specialization in transformer design and manufacturing
Global Reach – Products exported to Southeast Asia, the Middle East, Africa, South America, and beyond
Technical Expertise – A team of experienced engineers providing professional support from design to after-sales
Competitive Pricing – Optimized production processes delivering premium quality at affordable costs
Customer-Centric Approach – Flexible solutions tailored to individual project requirements
The three-phase oil-immersed transformer remains a cornerstone of modern power systems, offering unmatched reliability, efficiency, and longevity. As a trusted oil immersed transformer manufacturers in China, Jiangsu Xinhong Electrical Equipment Co., Ltd. is committed to delivering transformers that not only meet but exceed customer expectations.
Whether you require a standard distribution transformer, a custom-engineered unit, or a complete prefabricated substation solution, Xinhong Electrical is your reliable partner. We invite you to explore our product range and experience the Xinhong difference – where quality, innovation, and customer satisfaction come together.
