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What is Transformator ???

Transformator or Trafo is an electrical device that serves to change the

amount of voltage. A transformer  is an electrical device that transfers energy between two

or more circuits through electromagnetic induction. A varying current in the transformer's primarywinding creates a varying magnetic flux in the core and a varying magnetic field impinging on the

secondary winding. This varying magnetic field at the secondary induces a varying electromotive

force (EMF or voltage in the secondary winding. Ma!ing use of Faraday's "aw in con#unction

with high magnetic permeability core properties$ transformers can thus be designed to efficiently

change  A% voltages from one voltage level to another within power networ!s.

The Formula of Transformator

The number of coil (N) directly proportional with Voltage (V), but inverselyproportionalWith the current (I)  Np

 Ns=

Vp

Vs= Is

 Ip

 Eficiency ( )= Ps

 Pp X 100

Transformers are very efficient. &f it is assumed that a transformer is ) efficient (and this is a

safe assumption as transformers may be up to **) efficient then the power in the primary coil

has to be e+ual to the power in the secondary coil$ as per the law of conservation of energy.

Power in primary coil = Power in secondary coil

Characteristics of Transformator

http://en.wikipedia.org/wiki/Electromagnetic_inductionhttp://en.wikipedia.org/wiki/Electromagnetic_inductionhttp://en.wikipedia.org/wiki/Magnetic_fluxhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Electromotive_forcehttp://en.wikipedia.org/wiki/Electromotive_forcehttp://en.wikipedia.org/wiki/Electromotive_forcehttp://en.wikipedia.org/wiki/Faraday's_law_of_inductionhttp://en.wikipedia.org/wiki/Faraday's_law_of_inductionhttp://en.wikipedia.org/wiki/Permeability_(electromagnetism)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Magnetic_fluxhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Electromotive_forcehttp://en.wikipedia.org/wiki/Electromotive_forcehttp://en.wikipedia.org/wiki/Faraday's_law_of_inductionhttp://en.wikipedia.org/wiki/Permeability_(electromagnetism)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Electromagnetic_induction

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Primary Winding of transformer - which produces magnetic u when

it is connected to electrical source.

Magnetic Core of transformer - the magnetic u produced by the

primary winding, that will pass through this low reluctance path lin!ed with

secondary winding and create a closed magnetic circuit.

Secondary Winding of transformer - the u, produced by primary

winding, passes through the core, will lin! with the secondary winding.

 "his winding also wounds on the same core and gives the desired output

of the transformer.

#haracteristics $f Ideal "ransformer

%ero winding resistance& It is assumed that, resistance of primary as well as

secondary winding of an ideal transformer is 'ero. "hat is, both the coils are

purely inductive in nature.

Innite permeability of the core& igher the permeability, lesser the mmf

re*uired for u establishment. "hat means, if permeability is high, less

magneti'ing current is re*uired to magneti'e the transformer core.

+o lea!age u& ea!age u is a part of magnetic u which does not get lin!ed

with secondary winding. In an ideal transformer, it is assumed that entire amount

of u get lin!ed with secondary winding (that is, no lea!age u).

/ e0ciency& 1n ideal transformer does not have any losses li!e hysteresis

loss, eddy current loss etc. 2o, the output power of an ideal transformer iseactly e*ual to the input power. ence, / e0ciency.

The Type and Function of

Transformator

2tep 3p "ransformator (+p4+s)

 "he function of 2tep 3p "ransformator is to Increase the 1# voltage and #urrent

in circuit.

$n a step-up transformer there are more turns on the secondary coil than the

primary coil. "he induced voltage across the secondary coil is greater than the

applied voltage across the primary coil or in other words the voltage has been

5stepped-up6.

,tep-down Transformer (p/s

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 "he function of 2tep 7own "ransformator is to 7ecrease the 1# voltage and

#urrent in circuit.

 A step down transformer has less turns on the secondary coil that the primary coil. The induced

voltage across the secondary coil is less the applied voltage across the primary coil or in otherwords the voltage is 0stepped-down1.

The 2sed of Transformator 

 "ransformers are used to increase voltage before transmitting electrical

energy over long distances through wires. 8y transforming power to a

higher voltage transformers enable economical transmission of power anddistribution. #onse*uently, transformers have shaped the electricity

supply industry, permitting generation to be located remotely from points

of demans.

 "ransformer (transformer) used in electrical e*uipment, especially that

re*uire changes or ad9ustments magnitude of alternating voltage. :g radio

re*uires ; volts when the voltage of electricity ;; volts, it would re*uire

a transformer to convert alternating voltage to ;; volts alternating

voltage of ; volts. :amples of power tools that re*uire a transformer

are& "V, computers, copy machines, electrical substations, and so on.