WELCOME TO PRESENTATION ON GENERATOR

GENERATORGENERATORDEVELOPMENTDEVELOPMENT FIRST A.C GENERATOR CONCEPT WAS ENUNCIATED BY MICHAEL FARADAY FIRST A.C GENERATOR CONCEPT WAS ENUNCIATED BY MICHAEL FARADAY

IN 1831.IN 1831. FIRST TURBO GENERATOR WAS DEVELOPED BY SIR CHARLES A.PARSON IN FIRST TURBO GENERATOR WAS DEVELOPED BY SIR CHARLES A.PARSON IN

1889.1889. IN 1922 GENERATOR RATING WAS INCREASED TO 20MW AT 300 RPM BY IN 1922 GENERATOR RATING WAS INCREASED TO 20MW AT 300 RPM BY

USING SOLID FORGING & IMPROVED TECNIQUESUSING SOLID FORGING & IMPROVED TECNIQUES BY THE OUTBREAK OF SECOND WORLD WAR, IN 1939 LARGE GENERATOR BY THE OUTBREAK OF SECOND WORLD WAR, IN 1939 LARGE GENERATOR

WERE DEVELOPED OF 30 TO 50 MW AT 3000RPM WITH AIR COOLING.WERE DEVELOPED OF 30 TO 50 MW AT 3000RPM WITH AIR COOLING. PROBLEM OF ECONOMIC IN OF GENERATOR, DESIGNER WERE FACING PROBLEM OF ECONOMIC IN OF GENERATOR, DESIGNER WERE FACING

PROBLEM OF INCREASING IN RATING AND LIMITATION OF SIZE & WEIGHT.PROBLEM OF INCREASING IN RATING AND LIMITATION OF SIZE & WEIGHT. BREAK THROUHG TECHNIQUE OF USING HYDROGEN AS COOLING MEDIUM BREAK THROUHG TECHNIQUE OF USING HYDROGEN AS COOLING MEDIUM

INSTEAD OF AIR INCREASED THE RATING OF GENERATOR UPTO 275MW. INSTEAD OF AIR INCREASED THE RATING OF GENERATOR UPTO 275MW. FIRST OF HYDROGEN COOLED GENERATOR OF 60MW WAS INSTALLED IN FIRST OF HYDROGEN COOLED GENERATOR OF 60MW WAS INSTALLED IN U.K IN 1949. U.K IN 1949.

LARGEST: THDF 115/78 AT KKW TRILLO 1147 MVA, IN OPERATION SINCE 1988 LARGEST: THDF 115/78 AT KKW TRILLO 1147 MVA, IN OPERATION SINCE 1988 ALSO AT GOESGEN SINCE 1978.ALSO AT GOESGEN SINCE 1978.

THDF 125/78: 1250 MVA AT FRIMMERSDORF & AT BOXBERGTHDF 125/78: 1250 MVA AT FRIMMERSDORF & AT BOXBERG

GENERATORGENERATOR

PRINCIPAL: PRINCIPAL: A.C GENERATOR OR ALTERNATOR IS BASED UPON THE PRINCIPAL OF A.C GENERATOR OR ALTERNATOR IS BASED UPON THE PRINCIPAL OF ELECTROMAGNETIC INDUCTION GIVEN MICHAEL FARADAY IN 1831.ELECTROMAGNETIC INDUCTION GIVEN MICHAEL FARADAY IN 1831.

FIRST LAWFIRST LAW WHEN EVERY A CONDUCTOR CUT A MAGNECTIC FIELD EMF IS INDUCTED IN WHEN EVERY A CONDUCTOR CUT A MAGNECTIC FIELD EMF IS INDUCTED IN IT.IT.

SECOND LAW SECOND LAW EMF INDUCED IS DIRECTLY PROPORTIONAL TO RATE OF CHANGE OF FLUX EMF INDUCED IS DIRECTLY PROPORTIONAL TO RATE OF CHANGE OF FLUX LINKAGES.LINKAGES.

EQUATION :EQUATION :E = 4.44*E = 4.44*ΦΦ**F*N.F*N.

F = Pn/120F = Pn/120E = INDUCED EMFE = INDUCED EMFΦΦ = STRENGTH OF MAGNETIC FIELD IN WEBERS. = STRENGTH OF MAGNETIC FIELD IN WEBERS.F = FREQUENCY IN CYCLES PER SECOND OR HERTZF = FREQUENCY IN CYCLES PER SECOND OR HERTZN = NUMBER OF TURNS IN COIL,N = NUMBER OF TURNS IN COIL,P = NUMBER OF POLESP = NUMBER OF POLESn = REVOLUTION PER minuten = REVOLUTION PER minute

STATOR PMG

ROTOR

DAVR

MAIN EXCITER

P.T & C.T

LINE DIAGRAM OF 500MW GENERATOR

TO GENERATOR TRAFO

CC BOLTDIODE WHEELROTORSTATOR

0 25% 50% 75% 100%

9998.6498.5

98

97.5

97

LOAD IN MW : % FULL LOAD

η %

GENERATOR EFFICIENCY

TOTAL LOSSES IN GENERATOR TOTAL TO 6920 KW.

BREAK UP AS FOLLOWS:IRON LOSSES 600 KW.SHORT CIRCUIT LOSSES 2800 KW.EXCITATION LOSSES 1390 KW.WINDAGE LOSSES 1680 KW.BEARING & SEALS LOSSES 450 KW.

EFFICIENCIES FULL LOAD AND AT 75% FULL LOAD: 98.63%AT 50% FULL LOAD : 98.44 %.AT 25 % FULL LOAD: 97.5 %

GENERATOR EFFICIENCY

TOTAL LOSSES IN GENERATOR TOTAL TO 6920 KW.

GENERATOR EFFICENCY

AS LOSSES ARE DISSIPATED IN THE FORM OF HEAT (APPROX 6.9 MW).EFFECTIVE COOLING MEDIUM IS NEEDED

COOLING WITH HYDROGEN GASSTATOR WATER COOLING(PRIMARY WATER).

HYDROGEN GAS COOLING THE STATOR & ROTOR AIR GAP ROTOR WINDING.

PRIMARY WATER STATOR WINDING & BUSHINGS.

HYDROGEN

WHY HYDROGEN IS USED IN GENERATOR.HYDROGEN IS 13.6 TIMES MORE EFFECTIVE COOLING MEDIUM THAN AIR.

HYDROGEN BECOME EXPLOSIVE MIXTURE WHEN MIXED WITH AIR.

HYDROGEN PURITY SHALL BE MORE THAN 97%.

TO AVOID MIXTURE OF AIR & HYDROGEN GENERATOR IS SEALED WITH OIL AT THE SHAFT.

SEAL OIL SYSTEMSEAL OIL SYSTEM

• GENERATOR IS SEALED WITH THE OIL GENERATOR IS SEALED WITH THE OIL AT THE SHAFT AT THE SHAFT

• HYDROGEN IS DOUBLE SEALED WITH HYDROGEN IS DOUBLE SEALED WITH OIL CALLED AIR SIDE & H2 SIDE OIL CALLED AIR SIDE & H2 SIDE

• OIL PRESSURE IS MAINTAINED 1.5 OIL PRESSURE IS MAINTAINED 1.5 KSC MORE THAN HYDROGEN (3.5 KSC MORE THAN HYDROGEN (3.5 KSC).KSC).

CONSTRUCTION OF GENERATORCONSTRUCTION OF GENERATOR

• STATOR CORESTATOR CORE• STATOR SLOTSTATOR SLOT• STATOR WDG BARSTATOR WDG BAR• ROTOR SLOTROTOR SLOT

0.4

1.0

LAG

MVAR

LEAD

MW

0.70.85

0.9

0.95

0.95

100 300 500

450

RATEDMAX

H2 PRESS. 3.5 BAR

588200 400

CAPABILITY CURVE

ROTORROTOR

STATORSTATOR

HYDROGEN COOLING PATHHYDROGEN COOLING PATH

COMP BLADES

ROTOR SLOT COOLINGROTOR SLOT COOLING

I/LT.E

O/LE.E

VENTILATION SCHEMEVENTILATION SCHEME

WATER OUTLETS

H2 COMPRESSOR SIDE

A

B C

D

C.C BOLTC.C BOLT

PMG (PERMANENT MAGNETIC GENERATOR)PMG (PERMANENT MAGNETIC GENERATOR)

DIODE WHEEL RECTIFIERDIODE WHEEL RECTIFIER

MAIN EXCITERMAIN EXCITER

PRIMARY WATER PRIMARY WATER SYSTEMSYSTEM

TERMINAL BOXTERMINAL BOX

PHASEBUSHING

PW OUTLET

PW INLET

PHASE CONNECTOR

FLEXIBLECONNECTOR

PTFE HOSE

THDF TG : H2 SHAFT SEALEND SHIELDINSULATIONRING CARRIER

PACKINGSEAL RINGPRESS OIL

SHAFT

H2

SEAL OIL SYSTEMSEAL OIL SYSTEM

GENERATOR COREGENERATOR CORE

STATOR SLOT

SLOT WEDGE

TOP RIPPLE SPRING & PACKERS

SIDE RIPPLE SPRING

SEMI COND. WRAPPER

TOP BARBOTTOM BARHOLLOW CONDUCTORSOLID CONDUCTOR

SEMI-CONDUCTING

160

48

STATOR WINDING BAR

MICALASTIC INSULn.

HOLLOW STRIP

SOLID STRIP

45

50

4.6

58

1.6

5.85

1.3

ROTOR SLOT

COPPER ALLOY WEDGE

TOP PACKER

CONDUCTORSLOT LINERINTER-TURNINSULATIONBOTTOMPACKERS

196141

50.9

36.6

30

THDF: STATOR CORE - 2THDF: STATOR CORE - 2

PLATE SPRINGBASKETCORE BAR

SHUNT STUD

PRESSRING

D1330 D26305850 (5592)86 DUCTS

3

STATOR CORESTATOR CORE

CAGE

FLAT SPRING

CORE BAR

COMPRESSOR BLADESCOMPRESSOR BLADES