BIT Mesra Jaipur Summer Training on Manufacturing of Distribution Transformers
1. Birla Institute Of Technology
Mesra , Jaipur Campus
SUMMER TRAINING
[1st June – 28th July 2022]
Name- Shashank Bhadouria
EEE-VII -SEM
2. Contents…..
⮚ Objective
⮚ Company Profile
⮚ Basic Theories
⮚ Working Principle of Transformer
⮚ Distribution Transformer
⮚ Oil immersed distribution Transformer
⮚ Manufacturing of 3-Phase Distribution Transformer
⮚ Recommendations
3. objeCtives…..
⮚To apply theoretical knowledge in the practical field
⮚ To observe the manufacturing process of distribution transformer, testing
⮚Collecting knowledge regarding distribution transformer
⮚Developing skills and techniques relevant to our careers
4. Company profile….
⮚ Name: Crompton
⮚ Factory location: DLF Phase III, DLF Cyber City, DLF Phase 2, Sector 24, Gurugram,
Haryana
⮚ Ownership: Crompton Greaves Consumer Electricals Limited
6. Distribution
transformer…..
⮚ Used for distribution of electrical energy
⮚ Generally, operates at low voltage as less than 33KV in
industrial purpose and 440v-220v in domestic purpose
⮚ Three phase distribution transformers ,widely used in
11kv distribution
line to step down the voltage level.
7. Basic Theories..
7
1. Transformer is an electrical device that
transfer electric power from one circuit to
another
2. It does so without a change of frequency
3. It accomplishes this by electromagnetic
induction
4. Where the two electric circuits are in
mutual inductive influence of each other
13. Core material….
⮚ The mostly used core
material is CRGO-Cold
Rolled Grain Oriented steel
sheets of 3% of Silicon
⮚ Thickness of the CRGO
sheets usually 0.27 mm
⮚ Oxide coating is provided
for CRGO laminations to
reduce eddy current losses
15. Core jointing on Channel….
⮚ This is the simplest form of joints
⮚ The flux leaves and enters at the joint in
perpendicular
16. ⮚ Placing laminated sheets by hand or
hammer manually
⮚ No air gap between the joints of two
consecutive sheets
⮚ The entire assembly is done on a frame
commonly known as core channel
⮚ These frames being used as a clamping
support of the core assembly
17. Covering Copper wire with insulating tape…..
⮚ The mostly used
material for winding
wires or strips is
copper .
⮚ The copper wires or
strips are wrapped by
insulating tape or DPC
paper.
18. low voltage windings…..
Vertical machine is used to prepare the
LV winding
The helical and double layers
Number of turns varies on KVA
rating
19. low voltage windings…..
Starting End
Finishing End
Gape between two layers
⮚ Greater simplicity in fitting
cooling ducts
⮚ More even heat
distribution through the
windings
20. high voltage windings….
⮚ Horizontal machine is used to prepare the
HV winding
⮚ HV windings are of layered construction
⮚ The conductors are made of more round
wires, either with an insulating paper
⮚ The insulation between the layers
consists of DPC paper
28. Placement of HV
Winding:
Contd.
⮚This coil is placed on LV winding as
second layer of core
⮚ First LV coil then HV coil
⮚The gap between the LV and HV coil
is filled with runner of pressed board
31. Vector grouping.....
The vector grouping in NEL is Dyn
11:
⮚ Delta connected HV winding
⮚ Star connected LV winding
⮚ Neutral brought out
⮚ LV is leading HV with 30°
(11 o’clock)
32. taap Changer…..
⮚ Tapping is terminated
just bellow oil level
⮚ External
handle
⮚ Taping is done on HV
winding
⮚ Used to regulate the
output voltage to
required levels
Tap Changer
Exterrnal Handle
34. moisture Control…..
⮚ The whole active part of the transformer
in the heat chamber
⮚ Keeping it there for 72 to 96 hours with
a continuous heating temperature of
100° - 141° C to clean the moistures in it
⮚ Bringing it out after getting proper
insulation
36. Functions of Transformer Tank...
⮚ A container for the cooling
liquid
⮚ Providing shielding
against electromagnetic
field leakage
37. radiator….
⮚ Made steel like
tank
⮚Attached with the
tank
⮚Radiate the heat
from insulating oil
and makes the oil
cool
38. inserting the aCtive part into the tank…..
⮚ Whole active part is covered by
press board
⮚ Crane is used to lift the active part
⮚ By handling a chain the active part
is put slowly in the tank
39. bushings….
⮚ Counteracting the electrical field
strength
⮚ Insulating the incoming or outgoing
conductor into or out of the transformer
tank
Conductor
Insulator
40. Conservator….
⮚ Providing adequate space for
expansion of oil inside the tank
⮚ It also acts as a reservoir for the
insulating oil.
⮚ The oil level indicator indicates the
oil level
⮚ Oil level should not fall below
minimum limit
42. funCtion of transformer oil….
⮚ Providing dielectric strength
to the insulation system
⮚ Providing efficient cooling
⮚ Protecting of the transformer
core and coil from chemical
attack
43. QC tests….
Testing of Distribution Transformer:
⮚ Insulation test
⮚ Ratio test
⮚ Open circuit test
⮚ Short circuit test