An inductor is a passive electrical component that stores energy in a magnetic field when electric current passes through it. There are three main types: air core, ferromagnetic core, and variable inductors. Inductance is a measure of how much energy is stored in the magnetic field created by current flowing through the inductor. Self-inductance refers to the property of an inductor to store energy in its own magnetic field, while mutual inductance describes the magnetic field induced in one coil by another coil. Inductors are used in electric circuits, especially together with capacitors and resistors to create filters and for signal processing. They are also used in inductive sensors.

1. Applied Science & Humanities Department
SUBJECT : EEE- 2110005
TOPIC NAME: INDUCTOR
BRANCH : Computer Engineering- 07
GROUP NO. : 02

2. INDUCTOR

3. Basic Details
 A component in an electric or electronic circuit which
possesses inductance.
 An inductor, also called a coil or reactor, is a passive two-
terminal electrical component which resists changes in
electric current passing through it.
 It consists of a conductor such as a wire , usually wound
into a coil.

4.  Types of inductor:-There are mainly three types of
inductor,
1. Air core inductor
2. Ferromagnetic core inductor
3. Variable inductor

5. Inductance
 In electromagnetism and electronics, inductance is the
property of an electrical conductor by which a change in
current through it induces an electromotive force in both
the conductor itself and in any nearby conductors by
mutual inductance.
 The symbol of inductance is L.
 In the SI system , the measurement unit for inductance is
the henry, with the unit symbol H.

6.  Inductance is determined by how much magnetic flux
φ through the circuit is created by a given current i,
 The inductance changes with the current, in this more
general case inductance is defined as,

7. Self Inductance
 We consider a coil having N turns carrying a current of I
amperes. Let the flux produced be φ weber.
 The total magnetic flux linking with the coil due to current
I will be Nφ.This flux is produced due to current.

8.  i.e Nϕ α I
 N ϕ =LI
 𝐿 =
𝑁𝜙
𝐼
henry
 Since 𝑒 = −𝑁
𝑑𝜙
𝑑𝑡
 And Nϕ =LI
 𝑒 = −𝐿
𝑑𝐼
𝑑𝑡

9. Mutual Inductance
 We consider two coils that are placed close to each other.

10.  Let ϕ1 = flux in the primary coil
 I1 = current flowing in the primary coil.
 ϕ2 = flux induced in the secondary coil.
 I2 = induced current in the secondary coil.
 Flux ϕ2 is produced because of I1.
 ϕ2 α I1 or we can say
 ϕ2 = MI1
 where M is a constant for both the coils.
 Differentiating the above equation, we get

𝑑𝜙2
𝑑𝑡
= 𝑀
𝑑𝐼1
𝑑𝑡
 But emf induced in the secondary coil is 𝑒2 = −
𝑑𝜙2
𝑑𝑡
 so, 𝑒2 = −𝑀
𝑑𝐼1
𝑑𝑡

11. Stored Energy
 The energy stored by an inductor is equal to the amount of
work required to establish the current through the inductor, and
therefore the magnetic field.
 Induced emf, 𝑒 = 𝐿
𝑑𝑖
𝑑𝑡
 The energy dW = ei dt
 = 𝐿
𝑑𝑖
𝑑𝑡
𝑖 𝑑𝑡 = 𝐿𝑖𝑑𝑖
 The total work done,
 0
𝑊
𝑑𝑊 = 𝐿 0
𝐼
𝑖𝑑𝑖
 𝑊 = 𝐿
𝑖2
2
= 1
2
LI2

12. Properties
 A fully discharged inductor(no current through it) initially
acts as an open circuit(voltage drop with no current). After
charging fully to the final level of current, it acts as a short
circuit(current with no voltage drop).

13. Uses
 Inductors used a little bit in a few wireless applications,
but not much else.
 Inductors are used extensively with capacitors and
resistors to create filters for analog circuits and in signal
processing.
 Inductive sensors are used at nearly every intersection
with a traffic light to detect the amount of traffic and
adjust the signal accordingly.
 Like capacitors, inductors can be used for energy storage.

14. THANK
YOU