TRANSFORMERS

OVERVIEW» Definition» History» Working principle» Why do we use transformers?» Classification» Example» Manufacturing of transformers

Transformer is a power converter device that transfers energy between two electrical circuits by inductive coupling between two or more windings. It bring voltage up or down in ac electrical circuit and it can be used to convert

ac power to dc power.

DEFINITION

Single-phase distribution transformer in Canada use like a power supply facilities outside settlements, such as isolated houses.

The principle behind the operation of a transformer, electromagnetic induction, was discovered independently by Michael Faraday and Joseph Henry in 1830. But the first transformer used was about 1886 by William Stanly which was used in the electrification of great Barrington , Massachusetts.

HISTORY

Stanly’s First transformer

The transformer is based on two principles: first, that an electric current can produce a magnetic field (electromagnetism) and second that a changing magnetic field within a coil of wire induces a voltage across the ends of the coil (electromagnetic induction). Changing the current in the primary coil changes the magnetic flux that is developed. The changing magnetic flux induces a voltage in the secondary coil.

WORKING PRINCIPAL

Why do we use transformers?» To reduce the voltage or increase it between the

primary and the secondary sides

Why do we use transformers?

» To provide an economical way of transmitting power over the long distances.

» Converting from AC to DC.

1. According to method of cooling.Example: Self-air–cooled (dry type).

2. According to number of phases.Example: Single-phase.

3. According to insulation between windings. Example: Autotransformers.

4. According to method of mounting.Pole and platform transformers

5. According to purpose.Example: Constant voltage transformer.

6. According to service. Example: Distribution transformer.

CLASSIFICATION

Distribution transformer

Platform mounted transformer

AC to DC transformer

AC to DC Transformer in Details

» The coil Usually cupper and Aluminum are used to buildthe coil to reduce the resistance» winding

» The core

MANUFACTURING

MANUFACTURING» Video Linkhttp://www.youtube.com/watch?v=ANK--5Fu518

References1. Whelan, M. "The History of the Transformer." The

History of the Transformer. The Edison Tech Center, n.d. Web. 21 Dec. 2012. <http://edisontechcenter.org/Transformers.html>

2. http://www.mhprofessional.com/downloads/products/0071494626/CroftCh5.pdf

3. http://en.wikipedia.org/wiki/Transformer4. http://

www.powerwise.org.uk/ollieandsparky/teachers/OC3.html

5. http://www.youtube.com/watch?v=ANK--5Fu518