Step-Down Oil-Immersed Substation Transformer

With the continuous acceleration of the construction of the new power system, regional power grid framework optimization, expansion and upgrading of substations, and renovation of high-voltage transmission lines are all being comprehensively advanced. The stability, safety and efficiency of the core main equipment of high-voltage substations have become the key core for the reliable operation of the power grid. To adapt to the high-standard construction requirements of high-voltage transmission and transformation projects, relying on the mature research and manufacturing experience of power transmission and transformation equipment, the enterprise has launched a high-voltage transformer for power substations. With its high withstand voltage level, strong overload capacity, ultra-low loss, and ultimate safety and stability, it is widely applied in regional hub substations, industrial and mining dedicated substations, new energy boosting substations, and key projects of urban and rural main power grids, laying a core equipment barrier for the safe, stable, efficient, and economical operation of the high-voltage power grid.
As the core hub equipment of high-voltage substations, the power transformer undertakes the key functions of voltage transformation, power transmission and grid voltage regulation. The operating status of the equipment directly determines the power supply reliability of the entire power grid. In response to industry pain points such as weak withstand voltage performance, high load loss, poor adaptability to harsh working conditions, and high maintenance difficulty of traditional high-voltage transformers, the high-voltage transformer for power substations launched in this research has completed comprehensive technical upgrades. The equipment adopts high-purity high-magnetic-conductivity silicon steel sheet cores and an optimized laminating process, effectively reducing hysteresis loss and eddy current loss, precisely optimizing the winding structure layout, significantly improving the efficiency of power conversion, and all loss indicators exceed industry standards. The long-term operation energy-saving effect is remarkable, effectively reducing power transmission loss and maintenance energy consumption of the high-voltage power grid. It is specifically adapted to the working environment of high-voltage, large-load, and uninterrupted operation of substations. The equipment adopts a high-strength insulation structure and a multi-layer insulation protection design, combined with a vacuum drying and vacuum oil injection integrated process, eliminating internal moisture and impurity residues, with high insulation strength and excellent withstand voltage performance, capable of stably adapting to high-voltage transmission conditions, effectively resisting sudden conditions such as voltage fluctuations, instantaneous overload, and short-circuit impacts. At the same time, the equipment is equipped with a high-precision pressure release system, gas protection device, and temperature monitoring system, which can monitor the equipment operation status in real time, quickly issue warnings and provide precise protection in case of abnormal conditions, preventing the spread of equipment failures, and providing comprehensive protection for the safe and stable operation of the high-voltage substation system. In response to the complex operating environment of outdoor substations, the equipment adopts an integrated fully-sealed box structure, with precise overall welding and excellent sealing performance, effectively isolating rain, dust, dampness, salt fog and corrosive gases from invading, possessing strong resistance to moisture, dust, corrosion, aging and other capabilities, and can operate stably in extreme temperature differences, high humidity and rain, and sandstorms in the wild environment for a long time. The overall structure design is scientific and reasonable, with excellent seismic performance, uniform equipment operating temperature rise, low noise, and no leakage hazards, significantly reducing the frequency of later maintenance and achieving long-term low maintenance and high reliability operation.
The product strictly follows the GB1094 series power transformer national standards and power grid engineering construction norms, from raw material selection, core winding, winding assembly, vacuum treatment to the final factory test; each process implements a strict quality control system. Before leaving the factory, a complete set of type tests such as withstand voltage test, loss test, temperature rise test, sealing performance test, and short-circuit bearing capacity test are completed. The product quality is stable, performance is reliable, and it fully meets the engineering requirements of regular, high-intensity, and uninterrupted operation of high-voltage substations, and can be adapted to the construction, expansion, and renovation projects of high-voltage substations of all grades up to 110kV and below.
Currently, the process of upgrading the power grid framework, integrating new energy into the grid, and transforming the power grid intelligence is continuously accelerating, and the high-end, reliable, and energy-saving of high-voltage transmission and transformation equipment has become an inevitable trend of industry development. In the future, enterprises will continue to focus on technological innovation in core equipment for high-voltage power transmission and transformation, delve deeply into the research and development, iteration and process improvement of high-voltage transformers and complete sets of power transformation equipment, continuously create high-performance, low-energy consumption and high-security power core products, and fully empower key projects such as regional power grid optimization and upgrading, construction of new energy bases, and industrial power support. This will provide solid equipment support for the high-quality development of the new power system.

Recently, to comply with the development trend of the new power system towards green, low-carbon, energy-efficient, and safe and reliable, and to further adapt to the electricity demands of urban and rural power grid renovations, industrial production, new energy support, and municipal engineering, the new generation of high-efficiency oil-immersed distribution transformers has been officially launched on the market. The product, with its outstanding advantages such as ultra-low loss, stable operation, high safety, and wide adaptability, has become the preferred main equipment for current distribution network energy conservation renovation and power upgrade.
With the continuous advancement of the national carbon reduction strategy, energy conservation and consumption reduction, as well as quality improvement and efficiency enhancement, of power grid equipment have become the core direction of industry development. Traditional distribution transformers generally have problems such as high loss, unstable temperature rise, and cumbersome operation. The new generation of high-efficiency oil-immersed distribution transformers, through structural optimization, material upgrading, and process iteration, significantly reduce no-load loss and load loss, and are superior to the current national energy efficiency standards, effectively solving the pain points of high energy consumption and poor economic performance of traditional equipment, providing solid equipment support for the reduction of costs and improvement of power supply in the power system.
In terms of core performance, this high-efficiency oil-immersed distribution transformer uses high-magnetic-conductivity high-quality silicon steel sheets, low-loss iron core structure, and optimized winding design. The magnetic circuit is distributed reasonably, with lower loss and less operating noise. The overall temperature rise is uniform, and the overload resistance is strong, enabling long-term stable and efficient operation. At the same time, the product adopts a precise sealing structure and vacuum oil injection process, effectively preventing the intrusion of air, water vapor, and dust, with excellent insulation performance, outstanding resistance to aging, dampness, and corrosion, and the ability to fully adapt to complex working conditions such as outdoor, high humidity, dust, and large temperature differences.
In terms of safety and operation, the equipment is equipped with a complete protection structure, featuring reliable overheat, overload, and short-circuit protection capabilities, with a high safety coefficient. The overall structure is compact, and installation is flexible, and can be widely applied in urban and rural distribution networks, industrial parks, industrial and mining enterprises, photovoltaic and wind power support, municipal infrastructure, and other scenarios. Compared with conventional products, the high-efficiency oil-immersed distribution transformer has lower full-life-cycle energy consumption, lower failure rate, and lower operation and maintenance costs, truly achieving multiple values of energy conservation, safety, economy, and durability.
In the future, the enterprise will continue to focus on technological innovation and energy efficiency upgrades of power distribution equipment, continuously optimize the series of high-efficiency energy-saving distribution transformers, and with high-quality, low-energy consumption, and high-reliability power equipment, help the power grid achieve digitalization, greenification, and intelligentization upgrades, continuously empowering various industries with safe and stable power supply, energy conservation, and carbon reduction development.

Recently, our company's Three-Phase Hermetically Sealed Oil-Immersed Distribution Transformer has completed batch production and type testing. With its core advantages such as fully enclosed protective structure, ultra-low energy consumption, maintenance-free operation, and strong environmental adaptability, it provides high-stability core equipment for power transmission in various scenarios such as urban and rural power grids, industrial plants, new energy stations, municipal infrastructure, mining and chemical industries, etc., deeply aligning with the national dual-carbon strategy and the development requirements of intelligent and green distribution network transformation.

As the "energy hub" of the power transmission and distribution system, traditional oil-immersed transformers generally have oil reservoirs and breathing devices. During operation, the insulation oil is prone to contact with air, oxidation, and moisture absorption, requiring regular oil filtration, oil replacement, and testing. This not only incurs high operation and maintenance costs but also poses risks such as oil leakage, insulation aging, and frequent faults. The three-phase fully-sealed oil-immersed power transformer has completely revolutionized the underlying structure, eliminating the oil reservoir (oil pillow) and breathing devices. The box body adopts an overall full-welding sealed process, and the wave-shaped oil tank wall's elastic expansion compensates for the oil volume fluctuations caused by temperature changes, completely isolating the transformer oil circuit from the outside atmosphere, thereby eliminating the intrusion of moisture, dust, and corrosive gases at the root and significantly delaying the aging speed of the insulation oil and internal windings.

1. Core Technology Breakthrough, Leading Industry Performance

1. Fully sealed maintenance-free design, significantly reducing life cycle costs

The overall sealed welding structure blocks oxygen and water vapor from entering the oil tank, reducing the aging rate of insulation oil by more than 70%. After the equipment is put into use, there is no need for regular oil drainage, analysis, oil replacement, or oil filtration, truly achieving long-term maintenance-free operation; the integrated welding process significantly reduces the risk of oil leakage, avoiding oil pollution of the site, fire hazards, etc., and the equipment design service life can reach 25-30 years, significantly reducing long-term operation costs.

2. Efficient energy-saving iron core structure, practicing green and low-carbon development

The product uses three-phase symmetrical high-magnetic-conductivity cold-rolled silicon steel sheet wound iron core, with a balanced magnetic path and minimal magnetic resistance loss. The no-load loss and load loss are far superior to the national energy efficiency limit values, reducing the comprehensive loss by more than 15% compared to traditional S11 series transformers, with lower no-load current and lower operating noise. Under full-load conditions, the temperature rise is precisely controlled, and the long-term energy-saving benefits are prominent, meeting the standards for first-level energy efficiency products, helping enterprises reduce electricity consumption and complete energy-saving and consumption reduction assessment.

3. Strong adaptability to various working conditions, stable and reliable in complex environments

The equipment has full anti-corrosion, dust-proof, moisture-proof, and salt spray resistance performance, capable of coping with harsh scenarios such as high-humidity and salt spray areas along the coast, dust environments in mines, corrosive gases in chemical parks, and outdoor rainy and dusty conditions. The internal windings use high-strength insulation materials and vacuum oil injection technology, with an overall rigid fixation of the equipment body, excellent short-circuit impact resistance, and strong overload carrying capacity. It performs stably in industrial production lines with fluctuating loads, photovoltaic and wind power booster stations, and old transformer area grid renovation projects.

4. Compact modular structure, convenient and efficient installation and deployment

The wave-shaped heat dissipation oil tank integrates the cooling function, making the overall shape compact and regular, with a smaller占地面积. It supports core lifting for maintenance， can be directly installed on the ground， hung on poles， or pre-installed in box-type substations， suitable for 10kV/0.4kV mainstream power distribution systems， covering a capacity range of 30kVA-2500kVA， with high standardization and short delivery and on-site commissioning cycles.

In response to the national "dual carbon" development strategy, to meet the energy-saving, intelligent, and safe upgrade requirements of the new power system, and to assist in the energy-saving and carbon reduction transformation of the power grid and industrial sectors, the enterprise has newly developed and put into production an energy-saving non-ferrous alloy dry-type distribution transformer. This product breaks through the energy efficiency bottleneck of traditional transformers, relying on extremely low consumption, safety and fire prevention, environmental friendliness, maintenance-free, and high adaptability as core advantages, becoming the preferred energy-saving power equipment for urban and rural power grid renovations, new energy support, and high-end industrial and municipal engineering.

In the operation of the power system, traditional silicon steel sheet transformers have long suffered from high no-load losses, serious energy waste, and high operating noise, especially in scenarios where industrial parks, commercial buildings, and distribution rooms operate continuously for a long time, resulting in high overall electricity consumption costs. The newly launched energy-saving non-ferrous alloy dry-type distribution transformer adopts a new non-ferrous alloy strip as the core material of the iron core, overturning the traditional iron core structure process, with higher magnetic permeability and extremely low magnetic hysteresis loss. Compared with traditional dry-type transformers, the no-load loss has decreased by more than 60%, and the energy efficiency indicators far exceed the national first-level energy efficiency standard, achieving energy-saving and consumption reduction from the source and significantly reducing the long-term electricity operation costs for users.
In terms of performance and technology, the product adopts an epoxy resin vacuum casting process, with a compact and dense overall winding structure, high insulation strength, and excellent mechanical properties, possessing strong anti-short circuit, anti-shock, and anti-cracking capabilities. The equipment is oil-free, flame-retardant, fire-resistant, and explosion-proof, and during operation, it does not produce oil stains, exhaust gases, or combustion and explosion safety hazards. It completely avoids the safety risks of oil-immersed transformers due to oil leakage and fire, suitable for indoor distribution rooms, high-rise buildings, hospitals, schools, data centers, chemical industrial parks, and other enclosed and high-security-level power usage scenarios. At the same time, the equipment has stable operating temperature rise, extremely low noise, resistance to humidity, aging, and dust-free maintenance, and can adapt to complex operating environments with large temperature fluctuations, operating stably throughout the day.
Compared with conventional distribution transformers, this non-ferrous alloy dry-type transformer combines energy-saving and practicality, with a compact overall structure, small size, and convenient installation, without the need to reserve space for oil storage, heat dissipation, and fire protection, effectively saving power grid space resources. The equipment does not require daily oil replacement, filtration, or maintenance operations, significantly reducing the operational costs and human resource investment throughout the equipment's life cycle, with a longer service life and significant overall economic benefits. The product is widely applicable to various power distribution scenarios in urban and rural intelligent power grids, new energy photovoltaic and wind power support, industrial manufacturing, municipal public utilities, commercial buildings, etc., with strong universality and adaptability.
In terms of safety and quality, the product is developed and produced strictly in accordance with national power equipment standards, completing multiple strict quality inspections such as withstand voltage tests, loss tests, temperature rise detection, and insulation tests before leaving the factory. The quality is safe and controllable. The equipment includes a complete temperature control and overheat protection system that monitors the operating temperature in real time, issues early warnings for abnormal conditions, and provides comprehensive protection for the safe and stable operation of the power system.
Based on the new trend of green power development, in the future, the enterprise will continue to deeply research and innovate in energy-saving transmission and distribution equipment, continuously iterate and optimize non-ferrous alloy and energy-efficient series transformer products, with low-carbon, efficient, and safe high-quality power equipment, to help the power industry achieve green transformation, and continuously empower the construction of high-quality new power systems for various industries to achieve energy-saving and carbon reduction.