Classification of transformers:
Transformers are classified on the basis of core construction, frequency, and power. These are the three broad groups of transformers.
a) Core construction
b) Frequency
c) Power
a)Core construction:
On the basis of core construction transformers are classified on the basis of core arrangement and winding arrangement. So, there are two subtypes of one is core type transformer and second is shell types transformer.
1. Core type transformer:
The core of the transformer is made up of silicon steel or soft iron laminations. The horizontal part of the core is called yoke and the vertical portion of the transformer is called limb. In core type transformer most part of the core is encircled by windings. Core type transformer has a single magnetic circuit. For minimizing leakage flux half the primary and half the secondary are placed concentrically on each limb. The low voltage winding is on the inner side and high voltage winding is on the upper side. The coils used in the core type transformer is a cylindrical type. The coils are wound in the helical layer and separated from each other by paper or mica. The shape of the core may be square or rectangular depending upon the size of the transformer. The core is made up of thin laminations to reduce eddy current losses. In the case of core type transformer natural cooling is possible because the windings are uniformly distributed and core type transformer is used for low voltages.
2. Shell type transformer:
3. Berry types transformer:
Berry type transformer is also called as circular shell transformer
b) Frequency:
1. Power frequency transformer:
2. Audio frequency transformer:
3. Radiofrequency transformer:
c) Power:
1. Power transformer
Power transformers are used in conjunction with generators,
2. Distribution transformer