Transformers work on the principle of mutual induction to transform electrical energy from one circuit to another without a direct electrical connection. They consist of two coils wound around an iron core, with the primary coil connected to an alternating current source. As the current changes in the primary coil, it induces a changing magnetic field in the core which in turn induces an alternating current in the secondary coil. Transformers can step up or step down voltages depending on the ratio of turns in the primary and secondary coils. They are widely used in power distribution and electronics applications to efficiently transfer power or match voltages. However, some energy is lost through heat in the core and coils.

2. Contents:
What is Transformer
Principle of Transformer
Construction/Structure of Transformer
Working of Transformer
Types of Transformer
Efficiency of Transformer
Energy losses of Transformer
Uses of Transformer
About Transformer

3. What is Transformer ?
Electric device
Static device
The heart of Alternating Current System

4. Transform electrical energy from one circuit to another
without direct electrical connection.
Frequency remain fixed while voltage changes
Electromagnetic Induction.
Mutual Induction.

5. Principle of Transformer
Transformer works on the principle of
“Mutual Induction”
 According to that principle “Changing current in
(primary coil) induces emf in(secondary coil)”
Symbolically it is donated as:

6. Construction
Transformer consist of two coils of copper (insulated)
Coils are wound on same
core.
Primary coil
Secondary coil
No electrical connection
Magnetically linked

7. Working
A.C is passed through the primary coil it creates a
changing magnetic field in the iron core
Then changing magnetic field
induces A.C of the same
frequency in the secondary coil.
In this way current is
induced from primary coil
to secondary coil without any electrical connection.
A transformer has the ability to step up and step down
voltage.

8. Types of Transformer
A transformer has the ability to step up and step down
voltage. On these basis transformer are of two types:
Step up Transformer
Step down Transformer

9. Step up Transformer
The number of turns on the
secondary coil (Ns) is greater
then the number of turns on
primary coil (Np).
The induced voltage (Vs)
across the secondary coil is
greater than the applied
voltage (Vp) across the primary coil

10. Step down transformer
The no. of turns on the primary coil
are more then the number
of turns on secondary coil.
The induced voltage across
the secondary coil is less than
the applied voltage across the
primary coil.

11. Efficiency of Transformer
Power input = Power output
VpIp = VsIs


12. Energy losses in Transformer
Copper loss
Iron loss
Leakage of magnetic flux
Hysteretic loss
Magneto striation

13. Uses of Transformer
Use in Power Distribution

14. ….continues
Used in Radio sets, telephones,
loud speakers and electric bells etc
In voltage
regulator for T.V., refrigerator,
computer, air conditioner etc

15. About Transformer
Transformers range in size from RF transformers less
than a cubic centimeter in volume to power grid
weighing hundreds of tons.

16. Any Queries ??

17. Thank you