Introduction to Robotics in Mechanical Engineering.pptx
Transformers
1.
2. TransformerTransformer -- DefinitionDefinition
Transformer is a static device by means of
which an electric power in one circuit is
transformed to other circuit, without change
in frequency.in frequency.
It can increase or decrease the voltage in a
circuit but with a corresponding decrease or
increase in current.
3. Basic Working PrincipleBasic Working Principle
Mutual Induction between two
circuits linked by a common
magnetic flux.
Faraday’s Law of Electromagnetic
InductionInduction
“whenever a conductor is
placed in a varying magnetic field,
emf is induced in it, which is called
induced emf. If the conductor
circuit are closed, current is also
induced which is called induced
current.”.
5. Working Principle of TransformerWorking Principle of Transformer
In Transformer, there are two inductive coils,
which are electrically separated and magnetically
coupled.
If one coil is connected to ac source an
alternating flux is set up in the core it links
with other coil and produced mutually induced
alternating flux is set up in the core it links
with other coil and produced mutually induced
emf (Faraday’s Law).
If the second coil is closed, current flows in it –
Thus Energy is transferred.
First Coil Primary and Second Coil
Secondary
6. Transformer ConstructionTransformer Construction
• Core :
♦ Carries the flux produced by the winding
♦ It is either square or rectangular shape.
♦ The vertical portion of the core is called Limb
♦ The top and bottom horizontal portion of the core is
called Yoke.
♦ Made of high grade silicon steel laminations
♦ Laminated arrangements reduces eddy current losses.
♦ The laminations are insulated from each other by
using insulation like varnish.
8. Transformer ConstructionTransformer Construction
• Windings:
Coils used are wound on the limbs and insulated
from each other.
Windings carry the current and produce the
necessary flux
Primary and Secondary coils are insulated from
each other.
Coils are made up of Copper.
10. Conservator : takes up the expansion and
contraction of the oil without allowing it to
come in contact with the ambient air.
Explosion Vent :
A bent pipe
fitted on main
tank, which
Breather :
Extracts the
moisture from
air (using silica
gel crystals) and
does not allow
oil to come in
contact with the
moisture.
tank, which
bursts when
pressure inside
the transformer
becomes
excessive (which
releases the
pressure and
protects the
transformer)
11. Types of Single Phase TransformersTypes of Single Phase Transformers
Core Type Transformer
Shell Type TransformerShell Type Transformer
12.
13. 1. Core Type Transformers1. Core Type Transformers
Single Magnetic Circuit with 2 Limbs – Windings
placed on both the limbs Winding encircles
the core.
Cylindrical type coils are used with each layers
insulated by paper or mica.insulated by paper or mica.
Low voltage coil is placed near the core and High
voltage coil surrounds the low voltage coil.
Natural cooling is more effective.
Coils can be easily removed by removing the
laminations of the tope yoke, for maintenance
14. 2. Shell Type Transformers2. Shell Type Transformers
Double Magnetic Circuit with 3 Limbs –
Windings placed on central limb Core
encircles most part of the windings.
Natural Cooling doesn’t existNatural Cooling doesn’t exist
Difficult for maintenance, as for removing any
winding, large laminations to be removed
Preferred for Very High Voltage Transformers.
15. Comparison of Core and Shell TypeComparison of Core and Shell Type
TransformersTransformers