Dry-type transformers: High-efficiency and environmentally friendly power conversion equipment
In power systems, transformers are core equipment for voltage level transformation and ensuring efficient power transmission and distribution. Dry-type transformers, as a type of transformer that does not require insulating oil cooling, are widely used in urban power grids, high-rise buildings, industrial plants, and other scenarios with high safety and environmental requirements due to their outstanding advantages, such as fire and explosion protection, environmental friendliness, and ease of maintenance. They have become an important component of modern power systems.
Dry-type transformers use air or gas (such as SF₆) as the cooling medium. Their core structure mainly includes the core, windings, insulation materials, cooling fans, and casing. The core is made of high-permeability silicon steel sheets to reduce iron losses. The windings are mostly made of copper or aluminum wire, and the outer layer is wrapped with high-temperature-resistant insulation materials such as epoxy resin, which not only provides excellent insulation performance but also effectively resists mechanical vibration and chemical corrosion. The cooling system is usually equipped with axial or radial fans to dissipate the heat generated during operation through forced air cooling, ensuring stable operation of the transformer under rated load.
Compared to traditional oil-immersed transformers, dry-type transformers have significant performance advantages. First, dry-type transformers offer high safety performance. Because they contain no insulating oil, they avoid the safety hazards associated with oil-immersed transformers, such as oil leaks, fires, and explosions, making them particularly suitable for installation in densely populated areas or locations with high fire safety requirements. Second, they are environmentally friendly, producing no oil pollution, and the materials can be recycled after disposal, aligning with green environmental protection trends. Third, they have low maintenance costs. There's no need for regular oil level and quality checks or insulating oil replacements; only winding cleaning and cooling system checks are required, significantly reducing maintenance workload and costs. Furthermore, dry-type transformers are relatively compact, allowing for flexible installation. They can be placed directly near the load center, reducing transmission losses and improving power quality.
Its applications are extensive: in urban power distribution networks, it is used in substations and switching stations to achieve medium and low voltage transformation, ensuring electricity supply for residents and businesses; in high-rise buildings, shopping malls, hospitals, and other locations, it serves as a distribution transformer to meet fire safety and spatial layout requirements; in the industrial sector, it is suitable for precision machinery, electronic equipment, chemical enterprises, etc., providing stable power output and adapting to complex working conditions such as high temperatures and dust; in new energy power generation systems, such as wind power and photovoltaic power stations, it is used to raise the generated voltage to the grid voltage level, enabling grid-connected power transmission.
To ensure the long-term stable operation of dry-type transformers, daily maintenance should include regularly cleaning the winding surface to prevent poor heat dissipation; checking for aging and cracking of insulation materials; monitoring winding temperature and cooling fan operation to avoid overload operation; maintaining good ventilation around the equipment; and keeping it away from flammable and explosive materials. With the power industry's increasing demands for safety and environmental protection, dry-type transformers are continuously developing in terms of material upgrades (such as the use of new insulation materials) and energy efficiency optimization (such as reducing no-load losses) and will play an even more important role in future power systems.