What is the difference between a dry-type transformer and an oil-immersed transformer?

What is the difference between dry-type transformer and oil-immersed transformer?

Dry-type transformers rely on air convection for cooling and are generally used for small and medium-capacity transformers for lighting, electronic circuits and other small and medium-capacity transformers in high-grade areas such as office buildings and urban buildings, halls, pavilions and institutes. The ratio is 100,000V/400V for loads with rated voltages of 380V and 220V.

1, from the appearance, dry-type transformer can directly see the core and coil.

2, the lead form is not the same, dry-type transformer mostly use silicone rubber casing.

3, capacity and voltage are different, dry-type transformer is generally suitable for power distribution, the capacity is mostly below 1600KVA, the voltage is below 10KV.

4, insulation and cooling is not the same, dry-type transformers are generally insulated with resin, relying on natural air cooling.

Oil-immersed transformers rely on oil as a cooling medium, such as oil-immersed self-cooling, oil-immersed air-cooled, oil-immersed water-cooled and forced oil circulation. Generally used in thermal power plant boosting station of the main transformer, the ratio of 20KV/500KV, or 20KV/220KV, generally used in power plants to drive their own loads (such as coal mills, induced draft fan, blowers, circulating water pumps, etc.) of the plant transformer is also an oil-immersed transformer, which is the ratio of 20KV/6KV. oil transformer rated voltage of 3-35kV grade.

1, oil-immersed transformers can only see the transformer shell.

2, oil-immersed transformer most of the use of porcelain bushings.

3, oil-immersed transformer but can be from small to large to do all the capacity, voltage level also do all voltage.

4, oil-immersed transformer rely on insulating oil insulation, rely on insulating oil in the transformer internal circulation of the coil generated by the hot band to the transformer radiator (sheet) on the heat dissipation.

5, oil-immersed transformer due to ‘accident’ may have oil spray or leakage, resulting in fire, mostly used outdoors.

6, oil-immersed transformer price is low.

Applicable places

Dry transformer environmental protection, flame retardant, impact resistance and other advantages, and commonly used in indoor and other high requirements of the power supply and distribution places, such as hotels, office buildings, high-rise buildings and so on.

Oil-immersed transformer due to the need for fire protection, generally installed in a separate transformer indoor or outdoor.