It is designed to be completely closed to the atmosphere. The internal pressure of the transformer is adjusted during oil printing using special equipment. While the transformer is under load, it tolerates the volume expansion in the insulating liquid (oil), which is heated due to thermal effects, through the boiler in the wave wall structure, which has an elastic structure (expands-shrinks) and also performs cooling function. In order to be completely oil-filled (no air) in the transformer, oil pressing is carried out in special vacuum chambers. Core and coil structure is the same as transformer with expansion tank.
Advantages and Disadvantages
- Since it is closed to the atmosphere, the insulation oil does not come into contact with oxygen and insulation deterioration caused by oxidation is eliminated. Transformer life in terms of insulation; and therefore the life of the transformer is extended.
- It does not require any periodic maintenance except cleaning under normal conditions and use.
- As there is no expansion tank, its height decreases dimensionally. This provides an advantage in transformer centers where height is a problem.
- On-site intervention, maintenance and repair are less likely. The need for hermetic pressure adjustment with the necessary equipment under vacuum in every situation where the hermetic pressure setting is broken or will be broken is considered as a disadvantage.
Power Range: All standard and intermediate powers between 25 kVA and 2500 kVA
Voltage Range: At all voltage levels between 0-36 kV
Number of Phase: 1 phase or 3 phase options
Tap Type: Idle or on-load tap changer
Cooling Type: ONAN and / or ONAF
Place of Use: Indoor and / or External areas
Loss Class: Standard production class A (AoAk); optional according to customer needs
Conductor Type: Aluminum and / or copper
Terminal Type: Porcelain insulator, plug-in type, cable box, side outlet