Transformer

Transformers

·       Introduction

 An alternating transformer is a device  by which A.C. power at once voltage may be transformed into A.C. Power at another voltage . But The frequency is the same for the input and output of the circuit . As it does not consist of any moving part, so it is often called static apparatus . The Output voltage and current depend upon the number and turns of wires used in the primary and secondary winding of the transformer  . According to it , it is called step up and step down . If the secondary winding of the transformer has more turns than the primary winding , it is called step up T/R . This is used whenever it is necessary to increase voltage that is if the voltage is 110 volts and we want 220 volts , then a step up transformer of 110 and 220 will be used in the circuit depending upon the requirement of current also.

·       Working Principle Of a Transformer

When the two independent coil are wound on the opposite limbs of a common magnetic circuit of  the rectangular shape of soft iron laminated  cores and an alternating voltage is applied to winding No.1 which is known s primary winding , an alternating flux is produced in the magnetic circuit.

 

·       Types Of Transformer

1.     According to the construction

Core Type Transformer

Shell Type Transformer 

 Berry Type Transformer

2.     According to the system of winding  used in the transformer

Single Phase T/R

Three Phase T/R

Auto T/R

3.     According to system of cooling of the transformer

Natural Air blast cooled

Oil immersed self cooled

Oil Immersed Cooled

4.     According to use

Power Transformer

Distribution Transformer

Instrument Transformer

Auto Transformer