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
9. 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
10. 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
11. 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.
12. 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
13. MINOR INSULATION Insulation between individual turns &
between layers Conductor Insulation paper & cotton Air
insulated Transformer insulation used is glass tap
14. TRANSFORMER TANK Plain sheet steel Tank Tube Tank Radiator
Tank Tank with separate coolers
15. 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
16. FINAL ASSEMBLY Installation of active part and assembly of
accessories TRANSFORMER TANK
17. WORK SHOP
18. QUALITY TEST Design Process Time M/C size specification
Process of manufacturing Dimension specification Testing
specification