Why Are Laminations Used In Constructing The Field Core

To magnetize the core.

Why are laminations used in constructing the field core.

They are stamped from a pre material strip of the respective thickness and finished by a consequent annealing process to optimize the magnetic properties. For example two e stampings plus two end closing i stampings to give an e i core forming one element of a standard shell type transformer core. The laminations of required size and shape are stamped together to get a pole which is then bolted to the yoke. To be parallel to axis of the applied field.

A stator core is built up as laminations are placed side by side in order to make a complete circular or ringed layer. 1 3 field winding f1 f2 the field winding is wound on the pole core with a definite direction. These individual laminations are tightly butted together during the transformers construction to reduce the reluctance of the air gap at the joints producing. The next layer is laid offsetting each layer like a brick or cinder block wall.

Lamination is the technique process of manufacturing a material in multiple layers so that the composite material achieves improved strength stability sound insulation appearance or other properties from the use of the differing materials such as plastic a laminate is a permanently assembled object created using heat pressure welding or gluing. The rotor and the stator. Adding silicon to steel increases its electrical resistance improves the ability of magnetic fields to penetrate it and reduces the steel s hysteresis loss. Motor laminations are created by using electrical steel laminations.

This induced emf causes current to flow known as eddy current. Following farady s law when the core is rotated in a magnetic field a voltage or emf is induced in the coils. Silicon steel also known as electrical steel is steel with silicon added to it. If non oriented steel was used we would need a certain amount of magnetizing force to establish flux in the core i e.

The rotor has a ring shaped iron core with slots that hold coils or windings. Standard laminations are described in din en 61021 in a variety of sizes and grades. Laminations and core packages are used for small transformers and chokes from mains frequency to several khz. As it requires a definite shape and size laminated construction is used.

These lamination stampings when connected together form the required core shape.