1. SEMINAR
ON
POWER TRANSFORMER
PRESENTED BY:
ASIF AHMED KHAN

2. POWER TRANSFORMER

3. INTRODUCTION:
CORE MATERIAL
• Basic material are Alloy Steel having main
content Silicon & carbon
• Which increases permeability & reduces
losses

4. CONTD..
CRGO
(cold rolled grain
oriented silicon steel)
CRGOS shows excellent Magnetic properties.
The purpose of using CRGO is to reduce the
hysteresis losses.
So CRGOS is more used

5. Power transformer core

6. CORE AND ACTIVE PART
ACTIVE PART
•C.R.G.O. STRIPS
•1-STRIP HAS WIDTH OF 0.27 mm
•COIL OR WINDING ASSEMBLY
PROCEDURE
•Manufacturing of LIMB
•Core Insulation

7. CORE AND ACTIVE PART
• Removal of TOP FRAM for Coil assembly
• Winding insulation detail
• TOP YOKE FILLING
• VAPOUR PHASE OVEN
• HV & LV leads from top & bottom to the
bushings
• REGULATING COILS to the tap changer

8. TYPE OF WINDING

10. SPIRAL
• It is used 100 A& for low Voltage Winding
• Mechanically very strong
Helical
• Intermediate range of current
• Suitable for LV winding of large transformer

11. •Cross-over suitable of current not exceeding 20 A.
•Use for HV winding of small transformer
Continuous disc:
•No of turns wound radially over one another
•separated by spacers
•HV winding
•Mechanically strong
Cross over

12. Sandwich
• mostly used for shell type transformer
• Control leakage reactance
• HV & LV are near so leakage flux is reduced
• mmf of each section is same.

13. INSULATION
kinds of Insulations:
Major Insulation:
•Insulating between LV & core
•Also between HV & LV
•Insulating barriers between limbs, coils & core yoke
•Oil impregnated paper used as it has high dielectric
strength

14. MINOR INSULATION
• Insulation between individual turns &
between layers
Conductor Insulation
• paper & cotton
• Air insulated Transformer insulation used is
glass tap

15. TRANSFORMER TANK
• Plain sheet steel Tank
• Tube Tank
• Radiator Tank
• Tank with separate coolers

17. TRANSFORMER OIL
• Double purpose , cooling & Insulating
• Permittivity is 2.5
• Breakdown strength of oil used must be 50kv RMS
• Major disadvantage is sluging
• To overcome this, synthetic oil is prefered

18. FINAL ASSEMBLY
• Installation of active part and assembly of
accessories
• TRANSFORMER TANK

19. WORK SHOP

20. QUALITY TEST
• Design
• Process Time
• M/C size specification
• Process of manufacturing
• Dimension specification
• Testing specification

21. THANK YOU