note of Transformer

 

      Chapter 12 : Transformer

Dear, CTEVT STUDENTS….

IF WE WANT TO TRAVEL THE CURRENT FOR LONG DISTANCE , THEN WE HAVE TO USE TRANSFORMERS BETWEEN SOURCE OF ELECTRICITY(SUCH A KALIGANDAKI HYDROPOWER) AND DESTINATION OF ELECTRICITY(SUCH AS FAN, BULB OF YOUR HOME)

 

 

 

 

 

 

 

 

A transformer is a device that transfers electric energy from one alternating-current circuit to one or more other circuits, either increasing (stepping up) or reducing (stepping down) the voltage.

THE TRANSFORMERS ARE USED TO INCRESE OR DECRESE THE ELECTRIC VOLTAGE

 

In brief, a transformer is a device that

 

1.       transfers electric power from one circuit to another

2.       does so without changing the frequency

3.       It does this using electromagnetic induction and

4.       when the two electric circuits are mutually inductively influenced

Working principle of transformer:

 

 

 

-       If the primary coil have less turn and secondary coil

have more turn, the voltage will increase.

-       If the primary coil have more turn and secondary coil have less turn, the voltage will decrease.

-       The laminated core is the metal which is used to attract the magnetic field

 

Electricity is one of the biggest discoveries in human history, reshaping the planet dramatically. Today, we enjoy a variety of advantages brought about by harnessing this basic force of nature and transporting it to remote places. Faraday and Henry advanced electrical study in 1830 by connecting it to magnetism, which led to the discovery of electromagnetic induction. This discovery changed the world by paving the way for the development of alternating current generators.

The working principle of transformer is based on Faraday’s Law of Mutual Induction or Electromagnetic Induction, which happens between two circuits connected by a mutual magnetic flux. Let’s first investigate the mechanism of electromagnetic induction before moving on to the operation of transformer

 

TYPES OF TRANSFORMER

1.     Step Down Transformer:

A Step-down Transformer is a transformer that converts a high voltage at the primary windings to a low voltage at the secondary windings. In terms of the coil windings, a step- down transformer’s primary winding has more turns than the secondary winding.

 

2.   Step Up Transformer:

A step-up transformer is a transformer that increases the voltage from the primary coil to the secondary coil while managing the same power at the rated frequency in both coils. It converts low voltage & high current from the primary side to the high voltage & low current on the secondary side of the transformer.

 

3.   Isolation Transformer:

An isolation transformer is a transformer used to transfer electrical power from a source of alternating current power to some equipment or device while isolating the powered device from the power source, usually for safety reasons or to reduce transients and harmonics.

 

4 .Air-core transformers

 

Air-core transformers are designed to transfer radio-frequency currents—i.e., the currents used for radio transmission; they consist of two or more coils wound around a solid insulating substance or on an insulating coil form. Iron-core transformers serve analogous functions in the audio-frequency range.

 

 

 

 

Note prepared by : Mausham aryal