19-08-2013, 04:09 PM
MANUFACTURING OF TURBO GENERATORS
MANUFACTURING OF TURBO.docx (Size: 13.04 KB / Downloads: 45)
OBJECTIVE
The Project includes the assembly of Turbo-Generators (4-pole and 2-pole Generators) and various tests done at different stages and shown the performance characteristics.
OVERVIEW - B.H.E.L
BHEL is the largest engineering &manufacturing enterprise in India.
It is one of NAVARATNA’S in India.
Established 40 years ago.
In 1970s: At Hyderabad with Germany Collaboration 60MW Air Cooled & 110MW Hydrogen cooled. At present it has extended up to 150MW Air Cooled.
TURBO GENERATOR PRINCIPLE
The basic principle of rotating machine remains the same i.e. “Faraday’s laws of electromagnetic induction”.
Hence basic essential parts required in the Production of Power by the Electrical Generator are
A magnetic field
A Conductor / Coil
Relative motion / mechanical force
STATOR FRAME
The stator frame is horizontally split type and welded construction and supports the lamination core and the winding. Both the air duct pieces and welded radial ribs provide for rigidly to the stator frame.
These two things are provided to the stator frame to support the stator on the foundation. The stator firmly fixed to the foundation plates with bolt through the feet.
STATOR WINDING
TYPES OF WINDINGS
Open circuit and Closed circuit winding
Lap and Wave winding
Concentrated and Distributed winding
Full pitch and Fractional pitch winding
Single layer and Double layer winding
STATOR WINDING ASSEMBLY FOR TWO POLE
winding holder
Ring holder
Bottom bar placing
HV Testing
Top bar placing
HV Testing
I Transposition
Brazing
Wedges
HV Testing
Phase sequence testing
Impegration process
ROTOR CORE
Rotor shaft is a single piece solid forming manufactured from a vacuum casting.
Longitudinal slots for insertion of the field winding are milled into rotor body.
Rotor consists of electrically active portion .
60% of rotor body circumference has longitudinal slots which holds the field winding.
Rotor teeth at the ends of rotor body are provided with axial and radial holes enabling the cooling air to be discharged after cooling.
ROTOR WINDING
Rotor winding consists of series connected turns, each of which consists of two half turns connected by brazing in the end section.
Thickness of each strip made upto 10.5mm.
For ventilation purpose the slots are provided on the coil and on inter strip insulation layer on both sides of coil.
Laminated epoxy glass fibre fabric with nomex filter are used for slot insulation.
Slot wedges are made of high electrical conductivity material which are short circuted through rotor body and thus act as damper windings
CONCLUSION
Bharat Heavy Electrical Limited is the largest engineering and Manufacturing enterprise of is kind in the public sector in India. It ranks Among the top twelve organizations in the world, engaged in the Manufacturing of power generation equipment.
The sector is an important part in Turbo generators. The stator Core is assembled by the laminated sheets. The universal form facture type bar is more flexible and it’s life time more. We use the ROEBEL BAR Transposition for stator winding which is more advantageous . BHEL has acquiring the latest technology in the insulation system.
“Thus turbo generator is used mostly in paper, Sugar, Cement, Petrochemical, Fertilizers, Rayon industries etc”.