Hi friends in this video we are going to
see construction of a transformer
there are two basic parts
first is magnetic coke
and second windings or coils so let's
discuss magnetic or force
so the transformer magnetic code is like
this
this is called as a limb this is also
limb and this is called as a you know
what is the job of this magnetic or coal
provides path for magnetic flux
so maximum flux will be passing through
this cool hence there are two types of
losses that will occur inside the core
and those losses are hysteresis and
eddy-current
together these losses are called as a
magnetic losses or iron losses
now we need to construct or make a
course such a way that these two losses
are as low as possible how we can get
that through design so let's discuss how
to minimize hysteresis loss so generally
code is made up of high grade silicon
still this is the best magnetic material
how to choose the best magnetic material
magnetic material with
hi permeability this is what is provided
by this high grade silicon steel it is a
high permeability material earlier core
is made up of iron but now due to
advancement in material science we can
get a high permeability magnetic
material so that hysteresis loss is very
low so why we need this core made up of
a high permeability material in order to
minimize hysteresis losses
second loss is eddy-current
so how to reduce etiquette loss we make
core which is made up of
thin laminations
in order to minimize eddy current losses
because any current is happening because
of a with hybrid material so what we are
doing Orion we are providing the thin
laminations of 0.5 or 0.7 mm so that we
can have a width very very less and now
this thin laminations we can put one
over the other to form a step and this
laminations are insulated from each
other by insulation called as varnish so
how to form a code so this curve is
actually made up of thin laminations of
high magnetic material like this
and this laminations are insulated from
each other by varnish so this is how
core is for let us go to next part that
is winding or coins
windings are won over limbs of core like
this
so these are the windings this is called
as a primary winding because you are
going to connect a supplier to this and
here since load will be connected we
call this as a secondary winding
so what is the job of his winding
winding scary primary and secondary
current so electric current
passes through windings
so we need a material which will have
less resistivity so we will use copper
for carrying the current
so windings are made up of copper and
are warm on the legs of magnetic core so
there will be many number of turns on
this limb so obviously there is a risk
of touching to subsequent turns but that
we are going to avoid with the help of
insulation so remember these windings
are insulated from each other
since there is a length area of cross
section and some resistivity for this
material hence there will be some
resistance at the primary as your a
secondary site so current is passing
through this resistance give rise to I
square R losses so windings are
subjected to I square R losses which are
also called as copper losses so based on
the arrangement of CO and windings we
have two types of transformer
the first type is core type of transfer
core type of transformer is like this
this is cool
and these are windings this is secondary
winding and this is primary winding
now what is so special about this here
if you see corn is inside and then we
have windings so I can say the winding
encircles the core or you can say core
is surrounded by winding
let's see another type of transformer
that is shell type
so this is core and we have windings
like this
so what happened
here we are having two magnetic circuits
this is a forced magnetic circuit and
this is second magnetic circuit
so here if you see what happened there
is a core outside and windings are
inside so I can say the core encircles
the windings
or in other words you can say windings
are surrounded by
go
so if you see the structure properly
there are some differences between this
two first is obviously based on the
construction second this is having only
one magnetic circuit
whereas this shell type is having two
magnetic circuits suppose I want to
replace the windings it is very easy
over here just to take this part of a
core outside and take the windings out
and replace but replacing windings over
here is not a easy job
so based on the arrangement of core and
windings we have seen two types of
transformer normally very high voltage
transformers are of shell type thank you
