The Difference Between Dry-Type Transformers and Oil-Immersed Transformers

Dry-type transformers and oil-immersed transformers have distinct differences in structure, cooling methods, and application scenarios. Here is a detailed comparison:

1. Structure and Cooling Methods

• Dry-Type Transformer

• StructuralCoils and cores are typically insulated using epoxy resin when directly exposed to air.

• Cooling MethodPrimarily cooled through natural air circulation, fans are also used for assistance at times.

• Oil-Immersed Transformer

• StructureCoils and cores are immersed in insulating oil, and the oil tank is sealed.

• Cooling MethodPartial large transformers utilize oil pumps and fans for oil recirculation and natural air cooling.

2. Security and Maintenance

• Dry-Type Transformer

• SecurityOil-Free, Reduces Fire Risk, Ideal for High-Requirement Environments

• MaintainTypically low maintenance, but regular inspections of the insulation condition are required.

• Oil-Immersed Transformer

• SafetyThere is a risk of oil leakage and fire, additional protective measures are required.

• MaintainInsulation oil needs to be regularly inspected and replaced, which results in high maintenance costs.

3. Application Scenarios

• Dry-type Transformer

• AppliedIdeal for high-rise buildings, underground mines, subways, and other locations with strict fire safety requirements.

• Oil-Immersed Transformer

• ApplicableCommonly used in industrial settings outdoors or in rooms with dedicated transformers.

4. Noise and Environmental Impact

• Dry-type Transformer

• NoiseTypically lower in cost and more environmentally friendly.

• Environmental ImpactZero oil contamination, suitable for places with high environmental protection requirements.

• Oil-Immersed Transformer

• NoisePotential larger; noise abatement measures to be considered.

• Environmental ImpactThere is a risk of oil leakage, and waste oil must be handled.

5. Cost and Efficiency

• Dry-Type Transformer

• CostInitial costs are high, but maintenance costs are low.

• EfficiencyTypically, the efficiency is slightly lower than that of oil-immersed systems, but the difference is not significant.

• Oil-Immersed Transformer

• CostInitial costs are low, but maintenance fees are high.

• EfficiencyTypically slightly higher than dry-type transformers.

Summary

When selecting a transformer type, it is essential to consider various factors such as specific usage environment, space, budget, and safety requirements.