Single phase Transformer:

 Lesson Objective:

After going through this section students will be able to understand the following.

 necessity of transformers in power system.

 Construction and different cooling arrangements.

 properties of an ideal transformer and real transformer.

 e.m.f equation and meaning of no load & on load operation.

 basic working principle of operation under no load and also under loaded condition.

 phasor diagram under no load and on load condition at different power factor.

 exact equivalent and approximate circuit referred to any side of transformer.

 Different losses in transformer

 regulation and efficiency at different power factor. Concept of all day efficiency.

 O.C.Test and S.C.Test, estimate the losses, circuit parameters and performance.

 parallel operation, essential and desirable conditions and role of p.u. impedance on

load sharing.

 off load and on load tap changer

 Principles of single-phase Auto transformer –Comparison of weight and performance

with 2-winding transformer and their applications

Transformer- A piece of apparatus without continuously moving parts, which, by

electromagnetic induction, transforms alternating or intermittent electric voltage and

current in one winding into alternating or intermittent electric voltage and current in one or

more other windings, usually at different values of voltage and current.

Transformer is a device which:

1. Transfer Electrical power from one electrical circuit to another Electrical circuit.

2. It’s working without changing the frequency.

3. Work through on electric induction.

4. When, both circuits take effect of mutual induction.

5. Can step up or step down the level of AC voltage or AC Current.

6. Can’t step up or step down the level of DC voltage or DC Current.