Which is better, an oil type or dry type transformer?

2025,06,04

In the selection of substation equipment, oil-immersed transformers and dry-type transformers are the two most common types. They are suitable for different scenarios and have significant differences in safety, efficiency, maintenance costs, etc.

So, do you know which transformer is more suitable for your needs? As a professional power equipment supplier in Hubei, Hubei Jutai will make a detailed comparison from the aspects of technical characteristics, application scenarios, advantages and disadvantages, etc., to help you make a more informed choice.

The difference between oil-immersed and dry-type transformers

1. Different cooling and insulation methods

Oil-immersed transformers: mineral oil (transformer oil) is used as the insulation and cooling medium, the internal coil is immersed in oil, and the heat dissipation performance is excellent. It is suitable for large-capacity and high-voltage scenarios.

Dry-type transformers: air or epoxy resin is used as the insulation medium, no oil is required, and it relies on natural air cooling or forced air cooling for heat dissipation. It is suitable for places with high fire protection requirements.

2. Different applicable environments

Oil-immersed transformers: usually used in outdoor substations, large industrial electricity consumption and other scenarios, such as power plants, transmission networks, etc., and can withstand high load fluctuations.

Dry-Type Transformer: Mainly used in indoor power distribution, commercial buildings, subways, hospitals, data centers and other places with high requirements for fire prevention and environmental protection.

3. Maintenance and safety comparison

Oil-immersed Transformer: It is necessary to regularly check the oil level and oil quality, and prevent oil leakage. If the oil leaks, it may cause a fire risk.

Dry-type transformer: Maintenance-free design, no risk of oil leakage, stronger fire resistance, suitable for crowded areas.

Oil immersed transformer

Advantages

✔ Strong heat dissipation performance: Transformer oil has excellent thermal conductivity and is suitable for long-term high-load operation.

✔ Strong overload capacity: Suitable for main transformers in power systems and large-scale industrial electricity.

✔ Low cost: Suitable for projects with limited budgets at the same capacity.

Disadvantages

✖ Fire risk: Oil is flammable. If a short circuit or failure occurs, it may cause a fire. Comprehensive fire prevention measures are required.

✖ Complex maintenance: The oil level and oil quality need to be checked regularly, and the aging oil needs to be replaced, resulting in high operation and maintenance costs.

✖ Environmental issues: Transformer oil may pollute the environment and requires professional recycling and treatment.

Dry type transformer

Advantages

✔ High fire safety: Oil-free design, suitable for crowded places such as hospitals, shopping malls, subways, etc., in line with modern building fire protection regulations.

✔ Maintenance-free: No need to monitor oil, reduce operation and maintenance costs, and more economical for long-term use.

✔ Environmental protection and energy saving: No oil pollution, in line with the development trend of green electricity, Hubei Jutai's dry-type transformers use H-class insulation materials and have a longer life.

Disadvantages

✖ Weak heat dissipation capacity: Relying on air cooling, long-term high-load operation may lead to high temperature rise, and a reasonable ventilation system needs to be designed.

✖ High initial cost: Under the same capacity, the price of dry-type transformers is usually 20%-30% higher than that of oil-immersed transformers.

How to choose?

Choose according to the application scenario

Oil-immersed transformers are preferred:

Large substations, power plants, heavy industries and other places that require high loads and long-term operation.

Outdoor installation, environments with relatively low fire protection requirements.

Dry-type transformers are preferred:

Places with high fire protection requirements such as commercial buildings, data centers, hospitals, subways, etc.

Indoor power distribution, where space is limited and maintenance needs to be reduced.

Hubei Jutai: Professional transformer solution provider

Whether it is an oil-immersed transformer or a dry-type transformer, Hubei Jutai can provide customized solutions to meet the needs of different industries:

Oil-immersed transformer: suitable for large power systems and industrial electricity, cost-effective, stable and reliable.

Dry-type transformer: fireproof and explosion-proof, suitable for commercial and public facilities, low maintenance cost.

If you are planning the selection of substation equipment, please contact Hubei Jutai, we will provide you with professional consultation, product customization and after-sales support to ensure the efficient and stable operation of the power system!

Author:

Mr. jiawenhan

E-mail:

JT13797437282@gmail.com

Phone/WhatsApp:

+86 13797437282