PRESENTATION ON

POWER TRANSFORMER BY

BHEL

PRESENTED BY:-AJAY KUMAR MAURYA

CONTENTS OF PRESENTATION INRODUCTION TO BHEL ,JHANSI POWER TRANSFORMER DESIGN & DRAWING WINDING MANUFRACTURING CORE BUILDING COIL CORE ASSEMBLY RELACING OF CORE TERMINAL GEAR MOUNTING FINAL TANKING

BHEL(JHANSI UNIT) BHEL, JHANSI foundation was laid by late Mrs. Indira

Gandhi the prime minister on 9th Jan. 1974. The commercial production of the unit began in 1976-77. It is called second-generation plant of BHEL set up at an estimated cost of Rs 16.22 crores inclusive of Rs 2.1 crores for township.

BHEL,JHANSI is equipped with most modern manufacturing processing and testing facilities for the manufacture of power, special transformer and instrument transformer, Diesel shunting locomotives and AC/DC locomotives.

PRODUCT PROFILE OF BHEL,JHANSI

POWER TRANSFORMER A transformer is a static machine used for transforming power

from one circuit to another without changing frequency. Power Transformers refers to the transformers used between

the generator and the distribution circuits, and these are usually rated at 500 kVAand above.

Power Transformers are of following type: 1.Small power transformers 500 to 7500 kVA 2. Medium power transformers 7500KVA to 100 MVA 3. Large power transformers 100 MVA and above. 

COMPONENTS OF POWER TRANSFORMER CORE COIL INSULATION TAP CHANGER CONSERVATOR TANK COOLING SYSTEM

DESIGN & DRAWING SPECIFICATIONS OF TRANSFORMER SELECTION OF CORE DIAMETER SELECTION OF TYPE OF CORE SELECTION OF TYPE OF WINDINGS SELECTION OF TAPCHANGER CALCULATION OF NUMBER OF TURNS It is done by using emf equation: Volts per turn, Et=4.44BmAƒ

WINDING MANUFRACTURINGTHERE ARE FOLLOWING TYPE OF WINDINGS:- REVERSE SECTION WINDING SPIRAL WINDING HELICAL WINDING INTERLEAVED WINDING HALF SECTION WINDING COMPOSITE WINDING

REVERSE SECION WINDING SPIRAL WINDING

HELICAL WINDING INTERLEAVED WINDING

CORE BUILDING CRGO-Cold Rolled

Grain Steel is used to build the core. CRGO is used to reduce the hysteresis losses and the lamination made out of these sheets minimizes the eddy’s current losses

COMPLETE CORE

COIL CORE ASSEMBLY COIL CORE ASSEMBLY

INVOLVES THREE MAJOR STEPS

UNLACING OF CORE INSERTION OF WINDING RELACING OF CORE

UNLACED & RELACED CORE

TERMINAL GEAR ASSEMBLY Terminal Gear Assembly

done as described below: Cutting of leads as

required. Crimping/brazing of the

leads with cables. Brazing of bus bars. Fixing of different cleats. Crimping/brazing of

cables with terminal lugs. Mounting of the tap

changer/tap switch.

TAP CHANGER Tapchanger is used for

adding or cutting out turns of primary or secondary winding of the transformer.

THEY ARE OF TWO TYPES ON LOAD TAP CHANGER OFF LOAD TAP CHANGER

TRANSFORMER WITH TAP CHANGER

FINAL TANKING The transformer tank

provides the containment of the core and windings and for oil. It must withstand the forces imposed on it during transport.

Transformer tanks are almost constructed of welded boiler plate.

TRANSFORMER AUXILLARIES BUCHHOLZ RELAY TEMPERATURE INDICATOR PRESSURE RELIEF VALVE BUSHINGS OIL LEVEL INDICATOR SILICA GEL BREATHER

TESTING OF TRANSFORMER Preliminary Tests

Core insulation test Core loss Test

Final Tests Routine test

Measurement of winding resistance Measurement of voltage ratio Measurement of no load loss and current Measurement of insulation resistance

Type Test Temperature rise test Noise level test

COOLING SYSTEMVARIOUS TYPES OF

COOLING ONAN Type Cooling ONAF Type Cooling OFAF Type Cooling OFWF Cooling

COMPLETE TRANSFORMER

THANK YOU