You have often heard the name of the vortex when sometimes the water rotates round the same place in a pond, river or sea, or many times you have seen the wind moving round the same place in the same place, it is called vortex itself.
Something must be coming in your understanding of what the vortex current is. Now let's understand what is the mutual inductance in the transformer.
Mutual inductance
When we flow the current converted in one coil, a magnetic flux is generated in that coil. Now if another coil is placed near this coil, this magnetic flux will link the second coil, causing the second coil.
The induced electric carrying force is generated. This phenomenon is called reciprocal induction. This emf will continue to occur as long as the flux changes, so an altered current will be required to produce the effect of mutual inductance.
Interpretation of Mutual inductance
As shown in the figure, switch S with Battery A connects battery B with coil A, this coil is called primary coil. And place another coil B near it which is called secondary coil, in which we put a galvanometer.
When switch S is switched off, current I flows in the primary coil, by changing the value of resistance R we change the value of the current in the primary coil, causing the current in the primary coil to flow.
Converted current in the primary coil produces a magnetic flux converted from the coil.
This magnetic flux links to a nearby secondary coil, causing an induced electric carrying force in the secondary coil, resulting in a deflection in the thermometer. Which shows that the current has also flowed in the secondary coil.
If there is no change in the value of current in the primary coil, there will be no deflection in the galvanometer in the secondary coil.
If the value of the current converted to the primary coil is increased, the deflection is greater.
The direction of the induced current generated in the secondary coil is such that it opposes the change in the associated flux.
Eddy current loss in transformer
When we connect the primary winding to the alternating current supply in the transformer, this alternating current causes the alternating magnetizing flux in the transformer core and this flux links to the second winding causing a voltage in the secondary winding that results in this secondary Due to the load connected to it, a current flows in it.
Some of this alternating flux links to other parts of the transformer, such as steel core or iron body, etc., causing an emf to be localized in these parts as well.
Due to this emf, there is a current flow in these parts of the transformer. This current does not contribute to the external circuit of the transformer, due to which heat is generated in these parts of the transformer.
This heat is the loss of energy in the transformer. The heel of the transformer is called current loss.
To reduce vortex current losses, the transformer corso is made by adding several plates, (thin-thin) or leaves. Its core is called laminated.
A thin layer of varnish is applied to these cores, which shortens the path of the magnetic force lines. The core is less warm as currents erode.
Factors Affecting Eddy Current Loss
Vortex current losses depend on the following factors.
Maximum Flux Density (Bmax)
Core thickness t
Supply frequency (f)
At the volume V of the core.
It is clear from the above formula that the vortex current losses are proportional to the square of the thickness of the core t. If the thickness of the panels is reduced, the vortex current losses can also be reduced.
This is why transformers and other machines are made by thin cores. Core losses are determined by open circuit testing of transformers.