Let an alternating voltage source V1 be connected to the primary winding of a transformer. Now, due to the voltage source V1 ,an alternating current I starts flowing through N1 turns.
The current I through primary winding produces mmf equal to N1 I
The current I through primary winding produces mmf equal to N1 I
But from magnetic circuits basics, flux = mmf / reluctance
Therefore, Φ = N1I / reluctance
Since, the magnetic flux path reluctance remains almost constant throughout the operation of the transformer and N1 is also constant, therefore
Φ ∝ I
Therefore, an alternating sinusoidal flux is produced.
EMF Equation of a Transformer
Let the sinusoidally varying flux be expressed as
Φ= Φmax sinwt
where,
Φmax = maximum
value of core flux
w = 2Ï€f , angular
frequency of source V1
On Primary side
:-
By faraday’s law of electromagnetic induction, emf
induced in primary is
Showing that emf per turn in primary is equal to emf per turn
in secondary of a transformer. From this concept you can also find which side is high voltage
side (more number of turns) and which is low voltage side (less number of
turns) by just looking at a transformer.
Related concepts :-
(1) Transformer construction and its types - shell and core type transformer
(2) Open Circuit and Short Circuit test on Transformer
(3) Voltage regulation of transformer
(1) Transformer construction and its types - shell and core type transformer
(2) Open Circuit and Short Circuit test on Transformer
(3) Voltage regulation of transformer
