How to choose between dry-type transformers and oil immersed transformers? 5 considerations to help you make decisions

When choosing a transformer, the cooling medium is the key decision-making point. Dry type transformers and oil immersed transformers are the two mainstream in the market. With the improvement of urban construction and safety standards, how to choose has become particularly important. This article will compare these two technologies and provide you with a clear 2024 purchasing guide from the perspectives of safety, cost, and environment.

1.In depth analysis of oil immersed transformers

Oil immersed transformers are a traditional and mature technology. It uses mineral oil or other synthetic liquids as insulation and cooling media.

1.1 Working principle and advantages

The transformer winding is immersed in insulating oil. Oil can effectively isolate air and cool the winding. Its main advantages are high efficiency, low cost, strong overload capacity, and long lifespan. For high-capacity applications, it is usually the most cost-effective choice.

1.2 Potential Disadvantages and Risks

However, oil immersed transformers pose a risk of fire. Although modern technology has greatly improved safety, once leaked, mineral oil may become flammable and pollute the environment. Therefore, it is usually installed outdoors or in specialized fire-resistant rooms.

2.Have a comprehensive understanding of dry-type transformers

Dry type transformers use solid materials such as air or epoxy resin as insulation media, cooled by air convection or fans.

2.1 Working principle and advantages

Its biggest highlight lies in its high safety and environmental friendliness. Because it does not use oil, it fundamentally eliminates the risks of fire, explosion, and leakage pollution. In addition, it has a compact structure and is easy to maintain.

2.2 Potential Disadvantages and Limitations

However, dry-type transformers are usually more expensive, especially for high-capacity models. At the same time, its heat dissipation capability is not as good as oil immersed, resulting in a relatively large volume and slightly inferior overload capacity. In humid or dusty environments, it may require additional protective measures.

3.5 key considerations to help you make the right choice

You can evaluate two technologies from the following five aspects.

3.1 Installation location and environment

This is the primary factor. For indoor installation, especially in densely populated buildings such as hospitals, schools, commercial centers, and data centers, dry-type transformers are preferred because they are safer. For outdoor or independent substations, oil immersed transformers are widely used due to their economy and high endurance.

3.2 Safety and Fire Protection Requirements

If your project has extremely high requirements for fire prevention, the oil-free design of dry-type transformers provides an indisputable advantage. It is a mandatory requirement of many modern building codes and insurance companies.

3.3 Total Cost of Ownership

Oil immersed transformers have a low initial purchase cost, but may require more complex fire-fighting facilities. Dry type transformers have a high initial investment, but low maintenance costs and can save on fire safety expenses. You need to calculate the long-term total cost.

3.4 Maintenance and Reliability

Oil immersed transformers require regular inspection of oil quality and sealing. Dry type transformers are almost maintenance free, requiring only cleanliness and ventilation, and have extremely high reliability.

3.5 Energy Efficiency and Environmental Protection

Both have high-performance products. But dry-type transformers have more advantages in environmental protection, as they do not use mineral oil that may pollute soil and water sources.

Simply put, there is no absolute right or wrong choice, only the most suitable solution. If you pursue ultimate safety, indoor applications, and have sufficient budget, please choose dry-type transformers. If you are for outdoor applications, pursuing large capacity and minimum initial investment, oil immersed transformers are still a reliable choice. Before making a decision, it is essential to consult a professional engineer.

Luoyang Datang Energy Technology Co., Ltd. is a high-tech enterprise integrating R&D, manufacturing and supply of power equipment such as transformers, new energy components, distribution cabinets and inverters. With technological innovation as the core, we focus on creating high-reliability and high-performance power solutions to serve global customers. With a strict quality control system and international standard certification, we continue to output excellent products and enable customers to build safe and stable power systems.