The difference between indoor dry type transformer and oil cooled power transformer

In terms of capacity, there are more large-capacity oil-immersed transformers than dry-type transformers. Dry-type transformers are used in comprehensive buildings (basement, middle floor, roof, etc.) and densely populated places. The transformer must be installed on a separate substation. Transformers in boxes generally become boxes. Transformers typically use temporary power from outdoors. During construction, dry-type transformers and oil-immersed transformers can be selected according to the space. Oil-immersed transformers can be selected when the space is large. Dry-type transformers can be selected when the space is crowded. The area is humid and hot, and oil is handy. When dry-type transformers are used, forced air cooling must be provided.

one. With different packaging forms, dry-type transformers can directly see the iron core and coil, while oil-type transformers can only see the outer shell of the transformer. Different lead forms, dry-type transformers mostly use silicone rubber bushings, oil-type transformers mostly use porcelain bushings. Dry-type transformers with different capacities and different voltages are generally suitable for power distribution. Most of them are below 1600KVA and 10kV, and some are below 35kV. However, oil based transformers are very large from small to large and have very high voltages. The special high-voltage 1000kV test line under construction in my country must use oil-based transformers.

Insulation and heat dissipation of dry-type transformers are different. Dry-type transformers generally use resin insulation, natural air cooling, and large-capacity fan cooling. Oil-immersed transformers are insulated with insulating oil, which circulates inside the transformer to heat the heat sinks of the transformer. Dry-type transformers are mostly used in places where fire protection and explosion prevention are required. It is easy to use in large buildings and high-rise buildings. Dry-type transformers generally work at rated capacity, and oil-type transformers have better overload capacity. Transformers of the same capacity have different costs. The purchase price of dry-type transformers is much more expensive than that of oil-type transformers. The models of dry-type transformers generally start from SC (epoxy casting packaging), SG (open).