Lakhasly

1 Lecture 11: Inductors, RL filters and Transformers.Introduction to working principle of inductor In Electromagnetism, when an electrical current flows through a wire conductor, a magnetic flux is developed around that conductor.The Inductor An Inductor is a passive electrical component consisting of a coil of wire which is designed to take advantage of the relationship between magnetism and electricity as a result of an electric current passing through the coil.This effect produces a relationship between the direction of the magnetic flux, which is circulating around the conductor, and the direction of the current flowing through the same conductor.But unlike capacitors that store energy as an electric field, inductors store their energy as a magnetic field.Like a capacitor, inductors store energy.These lines of force start to extend further and further outward.The more current traveling through the wire the greater the amount of flux lines will be present.

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Lecture 11: Inductors, RL filters and Transformers.
The Inductor
An Inductor is a passive electrical component consisting of a coil of wire which is designed to
take advantage of the relationship between magnetism and electricity as a result of an electric
current passing through the coil.
Like a capacitor, inductors store energy. But unlike capacitors that store energy as an electric field,
inductors store their energy as a magnetic field.
Introduction to working principle of inductor
In Electromagnetism, when an electrical current flows through a wire conductor, a magnetic flux
is developed around that conductor. The more current traveling through the wire the greater the
amount of flux lines will be present. These lines of force start to extend further and further
outward. This effect produces a relationship between the direction of the magnetic flux, which is
circulating around the conductor, and the direction of the current flowing through the same
conductor.
But there is also another important property relating to a wound coil that also exists, it turns out
that if you have a field surrounding a conductor "wire" and it comes in contact with another
conductor "wire" then the flux lines will push electrons in a predictable direction. It is creating
an Electromagnetic Force (EMF), also known as voltage which is that a secondary voltage is
induced into the same coil by the movement of the magnetic flux as it opposes or resists any
changes in the electrical current flowing it.
If there was only one coil which is the primary wire then the EMF is induced on itself, generating
voltage in the opposite direction. Known as CEMF or Counter Electromagnetic Force or
counter voltage, this phenomenon is what makes the inductor possible.
In case, the magnetic field produced by self inductance is effecting another coil surrounded by
the first coil and producing voltage across the second coil, then is called Mutual
Inductance. Transformer works on Mutual Inductance concept.
As you increase current the magnetic fields start to expand outward moving through nearby coils.
When this happens, voltage is generated in the opposite direction making it harder and harder as
you increase current flow. When current has reached its peak, the inductor stops working until
there is a disruption in current flow like in the case of ripple current. So, when current has reached
its peak the inductor opposition to current flow stops because in order to generate voltage there
must be movement in either the magnetic fields or coil wires. Now if we were using a DC voltage
source then this would be the end of the inductors use.