Inductors PDF

INDUCTORS Emerson D. Rebibis INDUCTORS - coil-like structures found in electronic circuits - the coil is an insulated wire that is looped around the central core - a passive component used to decrease or control the electric spike by storing temporarily in an electromagnetic field, and then releas...

INDUCTORS Emerson D. Rebibis INDUCTORS - coil-like structures found in electronic circuits - the coil is an insulated wire that is looped around the central core - a passive component used to decrease or control the electric spike by storing temporarily in an electromagnetic field, and then releasing it back into the circuit.  INDUCTORS - it impedes or opposes any change in the amount of current flowing through it. Whenever the current across the inductor changes, it either acquires charge or loses the charge in order to equalize the current passing through it. It is also called a choke, a reactor, or just a coil. INDUCTANCE - Defined as the ratio of the voltage to the rate of change of current. - It is a result of the induced magnetic field on the coil Factors affecting inductance - The shape of the coil - The number of turns and layers of the wire - The space that is given between turns. - Permeability of the core material. - The size of the core The International System of Units of inductance is henry (H) named after Joseph Henry, and when we measure magnetic circuits, it is equivalent to weber/ampere. It is denoted by the symbol L. 1 H = one volt produced by a variation of inducing current of one ampere per second Different Types of Inductors 1. Iron Core Inductors – these are low-space inductors that have high power and high inductance value. But limited in high-frequency capacity. These are used in audio equipment.  Different Types of Inductors 2. Air Core Inductor – used when the amount of inductance required is low. It has no core, but the number of turns is more compared to inductors with core. It results in a high-quality factor. Ceramic inductors are often referred to as air-core inductor.  Different Types of Inductors 3. Iron Powder Inductor – the core is iron oxide, with very fine and insulating particles of pure iron powder. High magnetic flux can be stored in it due to the air gap. They are mainly used in switching power supplies.  Different Types of Inductors 4. Ferrite Core Inductor – ferrite materials are used as the core: Soft Ferrite and Hard Ferrite. Soft Ferrite – materials that have the ability to reverse their polarity without any external energy. Hard Ferrite – permanent magnets and their polarity will not change even when the magnetic field is removed.  Different Types of Inductors 5. Choke – is a type of conductor that is used mainly for blocking high-frequency alternating current in an electrical circuit. It will allow DC or low-frequency signals to pass.  Different Types of Inductors 6. Variable Inductor – lets the user control the inductance by changing the position of its ferrite core. Moving the core deeper into the coil, increases permeability, which increases the inductance. Moving the core further out of the coil lowers the permeability and the inductance.  Inductors in Series Inductors in Series When inductors are connected in series, their effective inductance increases. The current flowing through each inductor is the same. And the total voltage drop is the sum of the voltage drop across each inductor.  Inductors in Parallel Inductors in Parallel When inductors are connected in parallel, their effective resistance decreases. The total current is the sum of the current through each branch. The voltage across each inductor will be the same.