Transformers can be classified into different groups and types based on the following factors.
Type of core.
a. Core type transformer core.
b. Shell type transformer core.
c. Berry type transformer core.
d. Spiral type transformer core.
Method of cooling.
a. Natural cooling transformer.
b. Artificial cooling transformer.
c. Artificial cooling (water) transformer.
d. Mixed cooling transformer.
As per transformer ratio.
a. One to one transformer.
b. Step down transformer.
c. Step up transformer.
Based on number of phases.
a. Single-phase transformer.
b. Two-phase transformer.
c. Three phase transformer.
As per winding connection.
a. Star-star connected.
b. Star-delta connected.
c. Delta-delta connected.
d. Delta-star connected.
e. Open delta connected.
f. Scott connected
As per the size of the transformer.
a. Distribution transformer (upto 500 kVA).
b. Power transformer (above 500 kVA).
Based on function and utilization.
a. Auto transformer.
b. Potential transformer (instrument transformer).
c. Current transformer (instrument transformer)
