MANRAJ MEENA ELECTRICAL ENG. MNIT ,JAIPUR

MANUFACTURING PROCESS OF TURBO GENERATOR

History of development in BHEL

History:- Our countries first heavy electrical manufacturing plant was established in Bhopal in 1964.The main aim of establishing BHEL was to meet the growing power requirement of the country.

1971-72:- The company has been earning profits continuously since 1971-72.

RANK :- India’s laregest and world’s 7th largest manufacture of power plant equipments .

MAHARATNA:- maharatna status ,february 2013. 2013-14:- Today BHEL has 15 Manufacturing

Divisions ,9 Service Centers, 4 Power Sector Regional offices, 2 repairing centers .

Employees:- More than 50,000 employees are working in BHEL.

LOCATION OF BHEL PLANTS

NEW DELHI

KOLKATA

VARANASI

GOINDWAL

HARIDWARRUDRAPUR

JAGDISHPURJHANSI

BHOPAL

HYDERABAD BANGALORE

RANIPETTIRUCHIRAPALLY

•Electronics Division (EDN), Bangalore•Heavy electrical Plant (HEP), Bhopal•Industrial Valves Plant (IVP),Goindwal•Heavy Electrical Equipment Plant,Haridwar•Central Foundry Forge Plant,Haridwar•Heavy Power Equipment Plant,Hyderabad•Insulator Plant (IP), Jagdishpur•Centralised Stamping Unit & Fabrication Plant , Jagdishpur•Transformer Plant, Jhansi•Boiler Auxiliaries Plant (BAP), Ranipet•Component Fabrication Plant (CFP), Rudrapur•High Pressure Boiler Plant (HPBP), Tiruchirapalli•Seamless Steel Tube Plant (SSTP), Tiruchirapalli•Power Plant Piping Unit, Thirumayam•Heavy Plates & Vessels Plant (HPVP), Visakhapatnam

BHEL Projects Covered BHEL has Supplied over

2,25,000 MVA Transformer capacity until today.(2012-13)

Bhel has supplied more than 1,25,000 MW generating capicity equipments till today.( approx 55%)

The plant also have the capacity and technology to manufacture 800MW generators.

As announced BHEL is planning for 600 MW Solar Module Factory.

BHEL HARIDWAR

1.CENTRAL FOUNDRY AND FORGE PLANT

(CFFP)AREA:- 1.0 sq. Km

.

2.HEAVY ELECTRICALS EQUIPMENT PLANT

(HEEP)AREA:- 0.845 sq. Km

INTRODUCTION TO HEEP

Block-1:- (Electrical Machine Final Assembly) Block-2:- (Gas & Steam Turbine Fabrication Block) Block-3:- (Gas & Steam Turbine Manufacturing

Block) Block-4:- [CIM (Coil & Insulation

Manufacturing)Block] Block-5:- (Heat Exchangers Fabrication Block) Block-6:- (Stampings Block) Block-7:- (Wooden Packing works Block) Block-8:- (Heat Exchanger Tubes Block)

Block-1 (Electrical Machine Final Assembly)

Mainly Block-I is designed to manufacture Turbo Generators.

Products

Stator frameStator core

Rotor & Rotor Windings

Exciter

Block-1 (Electrical Machine Final Assembly)

The block-1 consists of 4 bays:- Bay-I (36*482 meters), Bay-II(36*360 meters) Bay-III (24*360 meters ) Bay-IV (24*360 meters ).

Bay - I &Bay- II Machining of the all major components is carried

out here . The boring and facing of stators are done on CNC horizontal boring machine

Block-1 (Electrical Machine Final Assembly)

Bay - III and Bay – IV Machining of the other small components is carried

out here. For handling and transporting the various

components over-head crane facilities are available. There is also a number of self-propelled electrically driven transfer trolleys for the inter-bay movement of

components.

Block-1 (Electrical Machine Final Assembly)

There are 3-different assembiles in block-1 .

ASSEMBLIES

STATOR ASSEMBLY

ROTOR ASSEMBLY

EXCITOR ASSEMBLY

Block-1 (Electrical Machine Final Assembly)

STATOR ASSEMBLY- stator parts are assembled here by using different

machine. Stator winding is done by placing stator on rotating installation.

ROTOR ASSEMBLY :- Rotor winding coils are assembled in rotor slots. The

pressing of overhang portion is carried out on special ring type hydraulic press, where as slot portion is pressed manually with the help of rotor wedges.

EXCITOR ASSEMBLY:- different excitor parts are assembled here, either

manully or using different machine. BHEL imports with german company SIEMENS.

FIG:- EXCITOR FOR 800 MW TURBO GENERATOR

Block-1 (Electrical Machine Final Assembly)

TEST BED:-

General assembly of Turbo Generator is done in the test bed.Rotor is inserted in the stator and assembly of end shields, bearings etc.are carried out to make generator ready for testing. Turbo Generators are tested as per standard practices and customer requirements.

New LSTG test bed have the facilites for testing

the turbo generator of ratings upto 1000 MW.

Block-1 (Electrical Machine Final Assembly)

TURBO GENERATOR

500 MW Turbo generators at a glance(Salient technical data)

• Rated output : 588 MVA , 500 MW • Terminal voltage : 21 KV • Rated stator current : 16 KA • Rated frequency : 50 Hz • Rated power factor : 0.85 Lag • Efficiency : 98.5%

IMPORTANT DIMENSIONS &WEIGHTS

500 MW TURBO GENERATOR :- Heaviest lift of generator (stator) : 255 Tons Rotor weight : 68 Tons stator dimensions :- 4.l2M(dia)x 8.83M(length) Rotor dimensions : 1.15M (dia )x 8.5 M( length) Total weight of turbo generator : 428 Tons

Transport through 24-Axle carrier beam railway wagon specially designed and manufactured at Haridwar.

COMPONENTS OF T.G.

STATOR – Stator frame Stator core Stator winding End covers

ROTOR – Rotor shaft Rotor winding Rotor retaining rings.

BEARINGSCOOLING SYSTEMEXCITATION SYSTEM.

STATOR FRAME

Stator body is a totally enclosed gas tight fabricated structure made up of high quality mild steel and austenitic steel.

It is suitably ribbed with annular rings in inner walls to ensure high rigidity and strength.

Basic purpose of stator frame to provide the support for stator core and to act as a pressure vessel for hydrogen gas in hydrogen –cooled T.G.

STATOR CORE The stator core is made of

insulated steel laminations. The thickness of the laminations and the type of steel are chosen to minimize eddy current and hysteresis losses

To remove the heat, a large number of space segments, are made along whole length of the core to pass the cooling agent through it and keep the stator core cool.

The stator core is then mounted in the stator frame.

STATOR WINDING

The stator has a three phase, double layer, short pitched and bar type of windings having two parallel paths. Each slots accommodated two bars.

Each bar consists of solid as well as hollow conductor with cooling water passing through the latter.

Alternate arrangement hollow and solid conductors ensure an optimum solution for increasing current and to reduce losses.

ROTOR SHAFT» Cylendrical rotor with 2 poles, speed 3000 rpm» Rotor shaft is a single piece forging manufactured from

a vacuum casting.» On 2/3 of its circumference( approximately) longitudinal

slots are provided to accommodate field winding

FIG:- FINISHED ROTOR

ROTOR WINDING

The winding consist of several coils inserted into the slots and the series connected such that two coils group to form one pole.

The conductors are made up of copper with silver content of approx. 0.1% for high strength at high temperature so that coil deformations due to thermal stresses are eliminated.

ROTOR RETAINING RINGS

It is the highly stressed component of T.G. The centrifugal forces of the end windings are

contained by rotor retaining rings. Retaining rings are made of non-magnetic high

strength steel in order to reduce the stray losses.

BEARINGS

Bearing require to rotate with minimum friction and vibration.

The turbo generators are provided with

pressure lubricated type bearing to ensure higher mechanical stability and reduced vibration in operation.

Jounral bearings are most commonly used in turbo generators.

COOLING SYSTEM

STATOR COOLING SYSTEM:- The stator winding is cooled by

demineralised water Water is fed from one end of the machine

by Teflon tube and flows through the upper bar and returns back through the lower bar of a slot.

Turbo generator requires water cooling arrangement over and above the usual hydrogen cooling arrangement.

COOLING SYSTEM

ROTOR COOLING SYSTEM:- Hydrogen is used as a cooling medium

in large capacity generator, generally in views of high heat carrying capacity and low density.

Cooling medium is required to circulate inside the generator in order to pick up the genrated heat,rotor fans are used for this purpose .

EXCITATION SYSTEM

STATIC EXCITATION:- • All components are static or stationary• Dc is directly supplied to the field of the main generator

through slip rings• the power supply to the rectifiers is from the main generator

EXCITATION SYSTEM

BRUSHLESS EXCITATION SYSTEM:- 1.)Pilot excitior 2.) Main excitior

Advantages of brushless excitation

No need of slip rings and brushes. Eliminates all the problem associated with

transfer of current via sliding contacts. Simple reliable and ideally suited for large

sets. Minimum operation and maintenance costs. Self generating excitation unaffected by

system faults or disturbances of shaft mounted pilot exciter.

Brush losses are eliminated

CONCLUSION

Practical training at BHEL Haridwar provided important knowledge in the field of construction of turbo- generators and their components.

Training at B.H.E.L. has proved quite faithful. It proved an opportunity for encounter with such huge machine like turbo-generators.

THANK YOU