How the construction of transformer is done and types of transformers used?

Construction of Transformer:

• The primary and secondary windings are insulated from each other.

• This assembly is erected inside a container.

• The four lugs are brought out through terminals.
• This is a simple construction of transformer for low voltage level and capacity.
• When the capacity goes high the voltage levels go high.
• Hence oil is used for insulation purpose as a cooling medium for transferring heat by convection method.

• When more heat has to be released, oil is  circulated through cooling arrangement place externally.
• The cooling arrangements are by simple radiation through the tubes or by forced air cooling.
• When the voltage level goes high, bushings are used to tap the supply from the windings.
• Bushings are insulated tubes with concentric conductors.

• Does we know the construction logic for simple and complex transformer.

Type of Transformers:

The transformers are classified into two types based on its construction.

They are :

1. Core type transformer.
2. Shell type transformer.

1. Core type transformer :

• In core type transformer, the winding surround a considerable part of the laminated core.
• In the diagram the primary and secondary winding's are shown at the opposite limbs of the core.
• But, practically the winding's are split into two halves and mounted on both the limbs to reduce leakage flux.
• The typical arrangement of core type transformer is shown with primary and secondary winding's.
• Considered the primary winding has low voltage (L, V) winding and secondary winding as high voltage (H,V) winding.
• The low voltage winding is easiest to insulate when comparing with the high voltage winding.
• So, the low voltage winding is placed closest to the core or earth point.
• The coil used in this type of transformer are former - wound.
• The shape of coil is cylindrical.
• These cylindrical coils are insulated from each other with the the help of materials like paper, cloth, micarta board etc.

2. Shell type transformer :

• In shell type of transformer the core surrounds a considerable portion of the winding's.
• The whole arrangement of the shell type transformer is shown in figure.
• In this type also the coils are former wound.
• They are multiplayer disc type generally wound in the form of pancakes.
• The different layers of multi-layer is risks from each other with the help of insulator.
• The whole coil arrangement as multi-layer discs with insulation spaces.
• These installations spaces are used for cooling purpose.
• This type of transformers are generally in simple rectangular type shape  or distributed type shape.

Read also working of transformer.