High Efficiency Oil-Immersed Power Transformer | Low Loss & Durable

Standard Professional Version (Suitable for General Product Pages)

Our oil-immersed transformer is a high-performance, reliable power transmission and distribution equipment, designed and manufactured in strict accordance with IEC 60076, GB 1094 and other international standards, widely used in global power grids, industrial parks, substations, residential areas, infrastructure projects, and industrial and mining enterprises. As a professional transformer foreign trade company, we focus on optimizing the core performance of oil-immersed transformers, combining advanced technology and mature manufacturing processes to provide customers with safe, efficient and durable power solutions.

The core of the oil-immersed transformer adopts high-quality cold-rolled grain-oriented silicon steel sheet, which is processed by step-lap lamination and vacuum drying technology. This design effectively reduces the no-load loss and no-load current of the transformer, improves the magnetic permeability and energy conversion efficiency, and ensures that the transformer operates with low energy consumption even in long-term light-load conditions. The high and low voltage windings are made of high-purity oxygen-free copper wire, which has excellent electrical conductivity and thermal conductivity, and is wrapped with high-temperature resistant insulation paper and insulating paint, forming a multi-layer insulation protection system to prevent insulation breakdown and ensure safe operation.

The transformer adopts high-quality mineral transformer oil as the insulation and cooling medium. The transformer oil has excellent insulation performance, high heat transfer efficiency and good oxidation resistance, which can effectively transfer the heat generated during the operation of the transformer to the outside, ensuring that the transformer operates within the safe temperature range. The tank body is made of high-strength carbon steel, which is processed by precision welding and anti-corrosion spraying. The hermetic structure design (optional) completely eliminates the risk of oil leakage, and the surface anti-corrosion treatment can resist the erosion of rain, snow, dust and corrosive gas, making the transformer suitable for long-term outdoor operation in harsh environments.

Our oil-immersed transformer is equipped with a complete protection system, including over-temperature protection, over-voltage protection, under-voltage protection, short-circuit protection, overload protection and oil level monitoring. When the transformer has abnormal operating conditions (such as over-temperature, oil level drop, short-circuit), the protection device will automatically alarm and cut off the power supply in time, effectively protecting the transformer and the entire power system from damage. The transformer has a compact structure, reasonable layout, easy transportation and installation, and the on-site commissioning time is greatly shortened, reducing the construction cost of the project.

With the advantages of low loss, high efficiency, low noise, long service life and strong environmental adaptability, our oil-immersed transformer is an ideal choice for global power transmission and distribution projects, and can provide stable and reliable power support for various fields. We support full customization according to customer needs, including voltage, capacity, tank structure, cooling method and protection functions, to meet the diverse power supply needs of different countries and regions.

Technical In-Depth Version (Highlight Principles & Core Technology)

As a professional manufacturer of oil-immersed transformers, we integrate advanced electrical technology and precision manufacturing processes to realize the optimization of transformer performance from the core principle to the structural design. The oil-immersed transformer operates based on the principle of electromagnetic induction: when the primary winding is connected to an alternating current, an alternating magnetic field is generated in the iron core, and the alternating magnetic field induces an electromotive force in the secondary winding, thereby realizing the conversion of voltage and current, and completing the transmission and distribution of electric energy. The key to improving the performance of the transformer lies in optimizing the iron core, windings and cooling system to reduce energy loss and ensure stable operation.

In terms of core technology, we adopt the "step-lap lamination" process for the iron core. The cold-rolled grain-oriented silicon steel sheet is cut into specific sizes and laminated in a step-by-step manner, which reduces the air gap between the silicon steel sheets, improves the magnetic permeability, and effectively reduces the no-load loss (iron loss) of the transformer. At the same time, the iron core is subjected to vacuum drying and impregnation treatment to remove moisture and impurities, enhance the insulation performance, and avoid core heating and energy loss caused by moisture. The no-load loss of our oil-immersed transformer is lower than the international standard, which can save a lot of electric energy for customers in long-term operation.

For the windings, we use high-purity oxygen-free copper wire with a purity of more than 99.99%, which has lower resistance and better electrical conductivity than ordinary copper wire, effectively reducing the load loss (copper loss) during operation. The windings are wound by a precision winding machine, with uniform turns and tight arrangement, and are wrapped with multi-layer high-temperature resistant insulation paper and insulating paint (Class A or Class F insulation), which can withstand high temperatures up to 105℃ or 155℃, ensuring that the windings will not be damaged due to overheating. In addition, the windings are subjected to vacuum pressure impregnation treatment, which makes the insulation layer more dense and uniform, improving the mechanical strength and short-circuit resistance of the windings. The short-time withstand current of our oil-immersed transformer can reach 25kA-50kA, which can effectively resist the impact of short-circuit current and ensure the safe and stable operation of the transformer.

The cooling system is the core part of the oil-immersed transformer, which directly affects the operating temperature and service life of the transformer. We adopt two cooling methods: natural oil circulation (ONAN) and forced oil circulation (OFAF), which can be selected according to the capacity of the transformer and the operating environment. The natural oil circulation cooling method relies on the density difference between hot oil and cold oil to realize the circulation of transformer oil, which is suitable for small and medium capacity transformers; the forced oil circulation cooling method uses an oil pump to force the circulation of transformer oil, which has higher heat dissipation efficiency and is suitable for large capacity transformers. The radiator of the transformer is made of high-efficiency finned steel pipes, which increases the heat dissipation area and improves the heat transfer efficiency, ensuring that the transformer operates within the safe temperature range (the top oil temperature does not exceed 95℃, and the average oil temperature does not exceed 85℃).

In terms of structural design, the transformer tank adopts a hermetic or semi-hermetic structure. The hermetic structure uses a rubber diaphragm to isolate the transformer oil from the outside air, preventing moisture and impurities from entering the oil, and avoiding oil oxidation and aging, thus extending the service life of the transformer oil and the transformer. The tank body is made of high-strength carbon steel, which is processed by precision welding, and the welding seam is tested by X-ray flaw detection to ensure no oil leakage. The surface of the tank body is sprayed with anti-corrosion paint (epoxy resin or polyurethane paint), which has strong anti-corrosion, anti-rust and anti-aging performance, and can adapt to harsh environments such as high temperature, high humidity, coastal salt spray and industrial corrosion.

Our oil-immersed transformer is also equipped with an intelligent monitoring system (optional), which can real-time collect parameters such as transformer oil temperature, winding temperature, oil level, voltage and current, and transmit the data to the monitoring center through wireless or wired communication. The system has automatic alarm and fault diagnosis functions. When the transformer has abnormal operating conditions, it can send an alarm signal in time, and the staff can remotely monitor and handle the fault, realizing unattended operation and reducing the labor cost of later management. All our products have passed strict factory tests, including no-load test, load test, short-circuit test, insulation test and oil quality test, to ensure that each transformer meets the international standard and has reliable quality.

High Efficiency & Energy Saving - Adopt high-quality cold-rolled grain-oriented silicon steel core and high-purity copper windings, optimize the core and winding structure, reduce no-load loss and load loss. The efficiency level reaches IE2/IE3, which is higher than the international standard, saving a lot of electric energy for long-term operation and reducing the operating cost of customers.

High Safety & Reliability - Equipped with a complete protection system (over-temperature, over-voltage, under-voltage, short-circuit, overload, oil level monitoring), which can timely alarm and cut off power when abnormalities occur, protecting the transformer and power system from damage. The windings adopt multi-layer insulation protection and vacuum pressure impregnation technology, with high insulation performance and short-circuit resistance, ensuring 24/7 safe and stable operation.

Strong Environmental Adaptability - The tank body is made of high-strength carbon steel with anti-corrosion spraying, and the hermetic structure (optional) prevents oil leakage and moisture intrusion. It can adapt to outdoor harsh environments such as high temperature, high humidity, coastal salt spray, dust and corrosive gas, and can operate normally in the temperature range of -40℃ to +50℃.

Low Noise & Quiet Operation - Optimize the core lamination process and winding structure, reduce the vibration and noise generated during operation. The noise level is ≤55dB (for small capacity) and ≤75dB (for large capacity), which meets the environmental noise standard and is suitable for residential areas, commercial buildings and other noise-sensitive places.

Long Service Life - High-quality transformer oil with good oxidation resistance and insulation performance, combined with hermetic structure design, can extend the service life of the transformer oil to 15+ years, and the overall service life of the transformer to 25+ years. The maintenance cycle is long, reducing the later maintenance cost.

Easy Installation & Transportation - Compact structure, reasonable layout, light weight (compared with traditional oil-immersed transformers), easy to transport by land, sea and air. The on-site installation is simple, and the commissioning time is short, which can reduce the construction cost and project cycle.

Full Customization - Support OEM/ODM customization, according to customer needs to customize voltage (1kV-35kV), capacity (10kVA-25000kVA), cooling method (ONAN/OFAF), tank structure (hermetic/semi-hermetic), protection functions and other parameters, to meet the diverse power supply needs of different countries and regions.

Environmentally Friendly - Adopt environmentally friendly transformer oil, non-toxic, non-polluting, no harmful substances, meet the EU RoHS and other environmental protection standards. The transformer oil can be recycled and reused, reducing environmental pollution.

International Certification - All products comply with IEC 60076, GB 1094, CE, ISO, UL and other international standards, have complete test reports and certification documents, and can easily enter the international market (Europe, America, Asia, Africa, etc.).

Intelligent Management - Optional intelligent monitoring system, real-time monitoring of transformer operating parameters, remote control and fault diagnosis, realizing unattended operation, improving management efficiency and reducing labor costs.

Core Technology: Step-lap lamination of cold-rolled grain-oriented silicon steel core, vacuum drying and impregnation treatment, low no-load loss, high magnetic permeability.

Winding Technology: High-purity oxygen-free copper wire, precision winding, multi-layer insulation protection, vacuum pressure impregnation, high short-circuit resistance and insulation performance.

Cooling System: Optional natural oil circulation (ONAN) and forced oil circulation (OFAF), high-efficiency finned radiator, good heat dissipation effect, stable operating temperature.

Insulation System: Class A (105℃) or Class F (155℃) insulation, high-temperature resistant insulation paper and insulating paint, strong insulation performance, long service life.

Tank Structure: High-strength carbon steel, precision welding, X-ray flaw detection, anti-corrosion spraying, hermetic/semi-hermetic design, zero oil leakage risk.

Protection System: Over-temperature, over-voltage, under-voltage, short-circuit, overload, oil level monitoring, automatic alarm and power-off, comprehensive protection.

Intelligent Technology: Optional remote monitoring system, real-time data collection, fault diagnosis, unattended operation.

Performance Parameters: Voltage range 1kV-35kV, capacity range 10kVA-25000kVA, frequency 50Hz/60Hz, short-time withstand current 25kA-50kA, protection grade IP54/IP65 (optional).

Oil Quality: High-quality mineral transformer oil, kinematic viscosity ≤12mm²/s (40℃), breakdown voltage ≥35kV, good insulation and heat dissipation performance.

Manufacturing Process: Strict quality control, precision processing, full factory testing (no-load test, load test, short-circuit test, insulation test, oil quality test), ensuring product quality.

Power Grid: High-voltage and low-voltage power transmission and distribution, substation construction, power grid upgrading and transformation.

Industrial Field: Industrial parks, factories, workshops, mining enterprises, chemical plants, metallurgical plants, providing stable power support for production equipment.

Residential & Commercial: Residential areas, high-rise buildings, shopping malls, hotels, hospitals, schools, providing safe and reliable power supply for daily life and business operations.

Infrastructure: Highways, railways, airports, ports, tunnels, municipal engineering, providing temporary or permanent power supply.

New Energy: Solar power plants, wind power plants, energy storage systems, matching power transmission and distribution needs.

Coastal & Harsh Environments: Coastal areas, high-humidity areas, dusty areas, industrial corrosion areas, adapting to harsh operating conditions.

Overseas Projects: International power grid projects, industrial projects, infrastructure projects, complying with international standards and adapting to local power supply needs.

1. Transformer Oil Advantage: Our oil-immersed transformer uses high-quality mineral transformer oil, which is refined by deep processing, with low viscosity, high breakdown voltage, good oxidation resistance and thermal stability. It can effectively insulate the windings and iron core, and transfer the heat generated during operation to the radiator. The transformer oil is non-toxic, non-polluting, and meets the environmental protection standards of various countries. It can be used for a long time without frequent replacement, reducing the later maintenance cost.

2. Core Loss Principle: The core loss (no-load loss) of the oil-immersed transformer is mainly composed of hysteresis loss and eddy current loss. The hysteresis loss is generated due to the magnetization and demagnetization of the silicon steel core when the alternating current passes through; the eddy current loss is generated due to the induced current in the silicon steel core. We adopt high-quality cold-rolled grain-oriented silicon steel sheet and step-lap lamination process, which can effectively reduce the hysteresis loss and eddy current loss, making the no-load loss of the transformer lower than the international standard.

3. Short-Circuit Resistance Principle: The short-circuit resistance of the transformer is mainly determined by the mechanical strength of the windings and the iron core. Our windings are made of high-purity copper wire, which has high tensile strength and mechanical strength. The windings are tightly wound and fixed by insulation brackets, and are subjected to vacuum pressure impregnation treatment, which makes the windings form a solid integral structure, which can effectively resist the electromagnetic force generated by the short-circuit current and avoid winding deformation or damage.

4. Anti-Leakage Technology: The tank body of our oil-immersed transformer adopts precision welding technology, and the welding seam is tested by X-ray flaw detection to ensure no welding defects. The hermetic structure uses a rubber diaphragm to isolate the transformer oil from the outside air, which not only prevents oil leakage, but also prevents moisture and impurities from entering the oil, avoiding oil oxidation and aging. The oil level gauge and oil drain valve are equipped with sealing gaskets to further ensure the sealing performance of the tank body.

5. Quality Control: We have a complete quality control system, from the purchase of raw materials (silicon steel sheet, copper wire, transformer oil, etc.) to the manufacturing process (core lamination, winding, assembly, testing), all links are strictly inspected. The raw materials must pass the incoming inspection, and the semi-finished products must pass the process inspection. The finished products must pass the full set of factory tests, including no-load test, load test, short-circuit test, insulation test, oil quality test and other items, to ensure that each transformer meets the international standard and has reliable quality.

Our transformers stand out in global market with 5 core strengths:

Superior Energy Efficiency：Equipped with high-conductivity cold-rolled silicon steel core and oxygen-free copper winding, our products reduce no-load loss by 15%-20% and load loss by 12% vs. national standards. Oil-immersed models feature corrugated radiators, 30% higher heat dissipation efficiency, suitable for 22℃-40℃ ambient temperatures.

Reliable Quality & Compliance：Fully compliant with IEC international standards and GB national standards, all units pass third-party type tests and factory inspections. With 0.01mm core lamination accuracy and F-class insulation, they excel in short-circuit resistance and weather resistance, ensuring over 80,000 hours of fault-free operation.

Flexible Customization for Global Needs：We offer full customization of capacity, transformation ratio, voltage level, and protection level. Perfect for PV, wind power distributed grid access, and adaptable to humid (Southeast Asia), low-temperature (Europe) and other harsh environments.

Cost-Effective & Fast Delivery：Factory-direct production eliminates middlemen, providing 10%-15% higher cost-performance than competitors. In-stock products are available immediately, and custom order lead time is 15% shorter than the industry average. Small-batch trial orders are supported to reduce customer risks.

One-Stop After-Sales Service：24/7 technical consultation, local after-sales docking for overseas orders, and free warranty maintenance/replacement. We also provide installation guidance and operation training, solving customer problems from pre-sales to after-sales.