Passive Component - Inductor

Passive Component - Inductor

INDUCTORS

• It is a coil wound on a core or former of a suitable material.

• Inductor is nothing but a coil wound on a core or former of a suitable material.

Fixed Inductor

The inductors are classified according to the type of cores used as follows:

(1) Air Core Inductor

• It consists of number of turns of wire wound on a former made of ordinary cardboard.

• Since there is air inside the former, the inductor is called as air core inductor.

• The air core inductor has no core losses even at high frequencies, and low inductance limited to value in µH or mH range.

(2) Iron Core Inductor

• Iron-core inductor is a coil of wire wound over solid or laminated iron-core.

• The iron core is laminated to avoid eddy current losses.

• The laminated iron core consists of thin iron laminations pressed together but insulated from each other.

• By putting the iron core inside the coil, the inductance of the coil increases by as many times as the relative permeability of iron. 

• Such inductor is also called as “choke”.

• The iron core inductors have very low losses at audio frequency, but the losses increase considerably at high frequencies even if the iron core is laminated.

(3) Ferrite Core Inductor

• It consists of coil of wire wound over solid core made of highly ferromagnetic substance called ferrite.

• Ferrite is solid material consisting of fine particles of iron powder embedded in an insulating binder.

• The ferrite core has minimum eddy current loss.

• The ferrite core has very low losses even at high frequencies. Example of this inductor is the antenna coils of transistor radio receiver.

4) Filter Chokes

• Filter chokes are the inductors used in smoothing pulsating current produced by rectifying ac into dc.

• A typical filter choke has many turns of wire wound on an iron core.

• Many power supplies use filter chokes of inductance value 5 to 20 H which are capable of carrying current up to 0.3 A.

5) Audio-Frequency Chokes

• Audio frequency chokes are used to provide high impedance to audio frequencies (60Hz to 5kHz).

• The audio-frequency chokes are smaller in size as compared to filter chokes and have lower inductance.

6) Radio Frequency chokes

• The radio frequency chokes (RFC) are basically used to block the radio frequencies in communication systems.

• The RFC chokes are having still smaller inductance. 


Team RRA 

Comments

Post a Comment

Popular posts from this blog

Passive and Active Electronic Components - Resistor

  Passive and Active Electronic Components   •         An electronic circuit is comprised of different individual components, grouped as passive components and active components .   •         The components which do not in themselves provide gain are called passive components . Eg. resistors, capacitors and inductors.   •         Components which provide amplification or switching are called active components . Eg. diodes, transistors and Ics.   RESISTORS   •         A resistor is a two terminal electrical or electronic component that opposes an electric current by producing a voltage drop between its terminals in proportion to the current, that is Ohm’s law: V = IR . •         The electrical resistance is equal to the voltage drop V across the resistor divid...
Read more

Concept of Alternating Current (AC) and Direct Current (DC)

  Concept of Alternating Current (AC) and Direct Current (DC)   An electric current is a flow of charged particles. Inside a copper wire, current is carried by small negatively-charged particles, called electrons . The electrons drift in random directions until a current starts to flow. When this happens, electrons start to move in the same direction. The size of the current depends on the number of electrons passing per second. Current is represented by the symbol I , and is measured in amperes , or ‘ amps ’, A. One ampere is a flow of 6.25 × 10 18 electrons per second past any point in a wire. That’s more than six million million million electrons passing per second. This is a lot of electrons, but electrons are very small and each carries a very tiny charge. In electronic circuits, currents are most often measured in milliamps , mA , that is, thousandths of an Ampere.   One terminal of a cell or battery is positive , while the other is negative . It is con...
Read more