The document discusses the manufacturing process of 600 MW turbo generator stator winding bars at BHEL Haridwar, India. It describes the 8 manufacturing blocks involved, including the coil and insulation manufacturing block. This block has 3 bays for manufacturing stator bars and coils of different machines. It also discusses the types of generators manufactured based on cooling systems, insulation classifications, and the manufacturing process which involves cutting, bending, transposition and testing of the bars. Key details of a 600 MW turbo generator are provided such as dimensions, weights and technical specifications.
ASM 2013 Fluxtrol Presentation - Innovations in Soft Magnetic Composites and ...Fluxtrol Inc.
http://fluxtrol.com
In induction hardening, thermal fatigue is one of the main failure modes of induction heating coils. There have been papers published that describe this failure mode and others that describe some good design practices [1-3]. The variables previously identified as the sources of thermal fatigue include radiation from the part surface, frequency, current, concentrator losses, water pressure and coil wall thickness. However, there is very little quantitative data on the factors that influence thermal fatigue in induction coils available in the public domain. By using finite element analysis software this study analyzes the effect of common design variables of inductor cooling, and quantifies the relative importance of these variables. A comprehensive case study for a single shot induction coil with Fluxtrol A concentrator applied is used for the analysis.
ASM 2013 Fluxtrol Presentation - Innovations in Soft Magnetic Composites and ...Fluxtrol Inc.
http://fluxtrol.com
In induction hardening, thermal fatigue is one of the main failure modes of induction heating coils. There have been papers published that describe this failure mode and others that describe some good design practices [1-3]. The variables previously identified as the sources of thermal fatigue include radiation from the part surface, frequency, current, concentrator losses, water pressure and coil wall thickness. However, there is very little quantitative data on the factors that influence thermal fatigue in induction coils available in the public domain. By using finite element analysis software this study analyzes the effect of common design variables of inductor cooling, and quantifies the relative importance of these variables. A comprehensive case study for a single shot induction coil with Fluxtrol A concentrator applied is used for the analysis.
Fluxtrol AlphaForm Moldable Magnetic Flux ConcentratorsFluxtrol Inc.
http://fluxtrol.com
AlphaForm is a Fast and Easy to Apply, Induction Magnetic Flux Concentrator. Fluxtrol’s AlphaForm high and low frequency, soft, moldable magnetic field concentrators can be used with any copper coil for quick, efficient results.
Gallery of Fluxtrol Magnetic Flux ConcentratorsFluxtrol Inc.
http://fluxtrol.com
Gallery of Fluxtrol Magnetic Flux Concentrator Machining, Induction Brazing, Process Improvement, AlphaForm, and Computer Simulation.
MAGNETIC FLUX CONTROL IN INDUCTION INSTALLATIONSFluxtrol Inc.
http://fluxtrol.com
It is well known that performance of some induction systems may be
significantly improved by application of magnetic flux controllers. They are used to
concentrate, shield and/or redistribute the magnetic field which generates power in the part. Theoretical and practical evidences are presented in the paper, which show that there is still significant potential for improvement in innovative and traditional induction technologies due to magnetic flux control. Utilizing magnetic flux controllers in heat treating processes results in excellent heat pattern control and improvement of parameters of inductors and entire power delivery systems. In melting systems, especially in the case of vacuum furnaces, cold crucible and other specialty furnaces, the magnetic control can provide energy savings, magnetic field shielding, shorter melting cycles and optimized field distribution for metallurgical processes. Comparison of different groups of materials for magnetic flux control (laminations, ferrites and Soft Magnetic Composites, aka Magnetodielectrics) is also presented in the paper. Several examples of magnetic flux control illustrate the presented material based on more than 20 years of R&D and practical experience of scientists and practitioners at Fluxtrol Inc.
Rautomead Newsletter issue 03
continuouscasting.com
For over 30 years Rautomead Limited has specialised in the design and manufacture of continuous casting equipment for non-ferrous metals and alloys. There are now more than 300 Rautomead machines in operation in over 45 different countries worldwide.
Rautomead plants are being successfully applied to production of oxygen-free copper, a wide range of copper-based alloys, precious metals and zinc. Forms include wire rod, straight length bars, flats and hollow sections. According to material and section, the casting process selected may be vertical upwards, vertical downwards or horizontal. The machines may be used either as integrated melting, holding and casting machines, or may be arranged to be fed with pre-alloyed molten metal.
The Rautomead Continuous Casting System is based on electric resistance heating of its furnaces, with graphite containment crucibles, graphite heating elements and casting dies. This technology is particularly suited for production of high purity, high quality oxygen-free copper and copper alloy wire rods (copper silver, copper magnesium, copper tin).
The upward casting equipment may be used to manufacture rods of all diameters between 8.0mm and 30mm diameter and is suitable feedstock for wire drawing and continuous rotary extrusion processes. End use applications include: superfine wire, automotive wires, contact wire and trolley wires for high speed trains, data communication cables, CTC and transformer strips as well as enamelled wires.
Rautomead’s R&D facility at the factory in Dundee (casting equipment, technicians, design and operational experience) is available to companies who wish to commission experimental and research work to develop technology and tooling for the manufacture and processing of new alloys and materials. Rautomead’s partnership with the University of Dundee provides access to sophisticated laboratory equipment as well as support with analytical evaluation and academic contributions to the R&D effort
Optimization Potential of Induction Heating Systems by Stefan Schubotz and Ha...Fluxtrol Inc.
As published in Heat Processing (March 2015).
Depending on workpiece and process parameters, induction heating of components requires a certain amount of power. By simulation, experiments and experience, this needed energy can be well anticipated and enables the dimensioning of the converter. Basically, cost of the converter increases with rising provided power. Due to increasing energy expenses, efficiency of the system plays an important role. In this article, the influences of different process parameters on the efficiency of an example are investigated and valuable potential for improvement is demonstrated, so that the heating process is implemented with minimum converter power.
Recognizing and Eliminating Flux Concentrator FailuresFluxtrol Inc.
http://fluxtrol.com
Overview:
• What are the failure modes of a flux concentrator?
• How do we improve the design to prevent the failure in the future?
• Examples of coil lifetime improvement by proper use of flux
concentrators.
Induction hardening is a process of hardening which is used to harden the particular or part to be required to be hardened. In this they used the faraday lows of induction.
Specification and Use of a Flux ConcentratorFluxtrol Inc.
http://fluxtrol.com
Overview:
Basics of Magnetic Flux Control
Effect of Flux Controllers on Different Coil Styles
Materials for Magnetic Flux Control
Influence of Magnetic Permeability
Selecting the Proper Flux Concentrator
Crankshaft Hardening Inductors
Hot Hydroforging of Lightweight Bilateral Gears and Hollow ProductsFluxtrol Inc.
Feasibility of making lightweight powertrain products with hot hydroforging of steel/low density material hybrid billets is explored. A bimaterial billet is designed such that a steel wall encloses a low density core 100%. Furthermore the low density core is selected among the materials that have lower melting or softening temperature than steel such as aluminum and glass. In hot hydroforging the bimaterial billet is heated to 1000-1200 C range similar to the conventional hot forging of steel. However, in hot hydroforging the core is in liquid or viscous state while steel shell is in solid state similar to the conventional hydroforming. During hot hydroforging the viscous/liquid core has negligible resistance to flow thereby providing a uniform hydrostatic pressure inside the steel and enabling a uniform deformation of the solid steel wall.
Increasing Inductor Lifetime by Predicting Coil Copper Temperatures PresentationFluxtrol Inc.
In recent years, there has been a significant increase in the customer demands for improved induction coil lifetime. This has led to several publications in recent years by induction tooling manufacturers [1-4]. The main conclusion in these papers is that besides mechanical crashes the cause of most induction coil failures is localized overheating of the coil copper due to insufficient cooling.
What is lacking from these publications is any way to determine what is sufficient cooling. In this paper, a scientific method for determining local copper temperatures will be presented. This will include evaluations of heat transfer coefficients for different sections of a multi-component inductor, dependence of heat transfer coefficient on water pressure and water passage cross-section, non-uniform power density distributions in various 2-D cross-sections and the resulting temperature distribution in the copper winding. The effects of duty cycle on optimal design will also be considered.
Fluxtrol AlphaForm Moldable Magnetic Flux ConcentratorsFluxtrol Inc.
http://fluxtrol.com
AlphaForm is a Fast and Easy to Apply, Induction Magnetic Flux Concentrator. Fluxtrol’s AlphaForm high and low frequency, soft, moldable magnetic field concentrators can be used with any copper coil for quick, efficient results.
Gallery of Fluxtrol Magnetic Flux ConcentratorsFluxtrol Inc.
http://fluxtrol.com
Gallery of Fluxtrol Magnetic Flux Concentrator Machining, Induction Brazing, Process Improvement, AlphaForm, and Computer Simulation.
MAGNETIC FLUX CONTROL IN INDUCTION INSTALLATIONSFluxtrol Inc.
http://fluxtrol.com
It is well known that performance of some induction systems may be
significantly improved by application of magnetic flux controllers. They are used to
concentrate, shield and/or redistribute the magnetic field which generates power in the part. Theoretical and practical evidences are presented in the paper, which show that there is still significant potential for improvement in innovative and traditional induction technologies due to magnetic flux control. Utilizing magnetic flux controllers in heat treating processes results in excellent heat pattern control and improvement of parameters of inductors and entire power delivery systems. In melting systems, especially in the case of vacuum furnaces, cold crucible and other specialty furnaces, the magnetic control can provide energy savings, magnetic field shielding, shorter melting cycles and optimized field distribution for metallurgical processes. Comparison of different groups of materials for magnetic flux control (laminations, ferrites and Soft Magnetic Composites, aka Magnetodielectrics) is also presented in the paper. Several examples of magnetic flux control illustrate the presented material based on more than 20 years of R&D and practical experience of scientists and practitioners at Fluxtrol Inc.
Rautomead Newsletter issue 03
continuouscasting.com
For over 30 years Rautomead Limited has specialised in the design and manufacture of continuous casting equipment for non-ferrous metals and alloys. There are now more than 300 Rautomead machines in operation in over 45 different countries worldwide.
Rautomead plants are being successfully applied to production of oxygen-free copper, a wide range of copper-based alloys, precious metals and zinc. Forms include wire rod, straight length bars, flats and hollow sections. According to material and section, the casting process selected may be vertical upwards, vertical downwards or horizontal. The machines may be used either as integrated melting, holding and casting machines, or may be arranged to be fed with pre-alloyed molten metal.
The Rautomead Continuous Casting System is based on electric resistance heating of its furnaces, with graphite containment crucibles, graphite heating elements and casting dies. This technology is particularly suited for production of high purity, high quality oxygen-free copper and copper alloy wire rods (copper silver, copper magnesium, copper tin).
The upward casting equipment may be used to manufacture rods of all diameters between 8.0mm and 30mm diameter and is suitable feedstock for wire drawing and continuous rotary extrusion processes. End use applications include: superfine wire, automotive wires, contact wire and trolley wires for high speed trains, data communication cables, CTC and transformer strips as well as enamelled wires.
Rautomead’s R&D facility at the factory in Dundee (casting equipment, technicians, design and operational experience) is available to companies who wish to commission experimental and research work to develop technology and tooling for the manufacture and processing of new alloys and materials. Rautomead’s partnership with the University of Dundee provides access to sophisticated laboratory equipment as well as support with analytical evaluation and academic contributions to the R&D effort
Optimization Potential of Induction Heating Systems by Stefan Schubotz and Ha...Fluxtrol Inc.
As published in Heat Processing (March 2015).
Depending on workpiece and process parameters, induction heating of components requires a certain amount of power. By simulation, experiments and experience, this needed energy can be well anticipated and enables the dimensioning of the converter. Basically, cost of the converter increases with rising provided power. Due to increasing energy expenses, efficiency of the system plays an important role. In this article, the influences of different process parameters on the efficiency of an example are investigated and valuable potential for improvement is demonstrated, so that the heating process is implemented with minimum converter power.
Recognizing and Eliminating Flux Concentrator FailuresFluxtrol Inc.
http://fluxtrol.com
Overview:
• What are the failure modes of a flux concentrator?
• How do we improve the design to prevent the failure in the future?
• Examples of coil lifetime improvement by proper use of flux
concentrators.
Induction hardening is a process of hardening which is used to harden the particular or part to be required to be hardened. In this they used the faraday lows of induction.
Specification and Use of a Flux ConcentratorFluxtrol Inc.
http://fluxtrol.com
Overview:
Basics of Magnetic Flux Control
Effect of Flux Controllers on Different Coil Styles
Materials for Magnetic Flux Control
Influence of Magnetic Permeability
Selecting the Proper Flux Concentrator
Crankshaft Hardening Inductors
Hot Hydroforging of Lightweight Bilateral Gears and Hollow ProductsFluxtrol Inc.
Feasibility of making lightweight powertrain products with hot hydroforging of steel/low density material hybrid billets is explored. A bimaterial billet is designed such that a steel wall encloses a low density core 100%. Furthermore the low density core is selected among the materials that have lower melting or softening temperature than steel such as aluminum and glass. In hot hydroforging the bimaterial billet is heated to 1000-1200 C range similar to the conventional hot forging of steel. However, in hot hydroforging the core is in liquid or viscous state while steel shell is in solid state similar to the conventional hydroforming. During hot hydroforging the viscous/liquid core has negligible resistance to flow thereby providing a uniform hydrostatic pressure inside the steel and enabling a uniform deformation of the solid steel wall.
Increasing Inductor Lifetime by Predicting Coil Copper Temperatures PresentationFluxtrol Inc.
In recent years, there has been a significant increase in the customer demands for improved induction coil lifetime. This has led to several publications in recent years by induction tooling manufacturers [1-4]. The main conclusion in these papers is that besides mechanical crashes the cause of most induction coil failures is localized overheating of the coil copper due to insufficient cooling.
What is lacking from these publications is any way to determine what is sufficient cooling. In this paper, a scientific method for determining local copper temperatures will be presented. This will include evaluations of heat transfer coefficients for different sections of a multi-component inductor, dependence of heat transfer coefficient on water pressure and water passage cross-section, non-uniform power density distributions in various 2-D cross-sections and the resulting temperature distribution in the copper winding. The effects of duty cycle on optimal design will also be considered.
Introduction to Computer Hardware
Case
Power switch
Reset switch
Hard drive
Floppy
CD/DVD
Zip drive
Serial ports
Parallel port
USB port
Keyboard/mouse
Network card
Modem
Sound card
Video card
RAM
Motherboard
Bus
Fan
Cables
ppt on coil and insulation manufacturing block, BHEL, haridwar
manufacturing process of stator bar by bhel for practical training or industrial training.about bhel
Condition monitoring of rotating electrical machinesAnkit Basera
Condition monitoring of rotating electrical machines, Construction, Operation, Types, Specification Of Electrical Machines, Different Failure Modes Of Electrical Machines, Failure Modes And Root Causes In Rotating Electrical Machines
This is a complete guide on Hollow conductors which are used at Power Plants for AC systems.
This is a training report on Bus Ducts. This was presented at Sri Balaji College of engineering and technology by Ajay Meena.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
Governing Equations for Fundamental Aerodynamics_Anderson2010.pdf
MANUFACTURING PROCESS OF 600 MW TURBO GENERTOR STATOR WINDING BAR
1. MANUFACTURING PROCESS OF 600 MW
TURBO GENERTOR STATOR WINDING
BAR
Presented By: Shubham Kulshreshtha(1301421092)
SRMS College of engineering & technology,
Bareilly
BHEL HARIDWAR
2. INTRODUCTION
In 1956 India took a major step towards the establishment of its
heavy engineering industry when BHEL, the first heavy electrical
Manufacturing unit of the country was set up at Bhopal.
BHEL's Heavy Electrical Equipment Plant (HEEP) was set up
in technical collaboration with USSR, for the manufacturing of
power plant equipment.
In 1976, BHEL entered into a collaboration agreement with
M/s Kraftwerk Union, AG of Germany for design,
manufacturing, erection and commissioning of large size
steam turbines.
More than 40 percent of the country's electrical energy is
generated from the power equipment supplied by BHEL,
Haridwar.
3. MANUFACTURING BLOCKS:
.
BLOCK I: ELECTRICAL MACHINE BLOCK, IS DESIGNED TO
MANUFACTURING OF TURBOGENERATORS
BLOCK II: FABRICATION BLOCK
BLOCK III: TURBINE BLADE BLOCK
BLOCK IV: COIL & INSULATION MANUFACTURING &
APPARATUS & CONTROL GEAR MANUFACTURING
BLOCK
BLOCK V: FEEDER BLOCK AND KNOWN AS FABRICATION
AND FORGE BLOCK
BLOCK VI: STAMPING AND DIES MANUFACTURING BLOCK
BLOCK VII: WOODWORKING BLOCK
BLOCK VIII: HEAT EXCHANGER BLOCK, IS DESIGNED TO
MANUFACTURE HEAT EXCHANGER UNIT FOR
STEAM TURBINES.
4. COIL & INSULATION MANUFACTURING
SHOP (BLOCK-IV)
Block-4 is a feeder block for insulating items,
winding with class-B Bituminous insulation and sheet
metal components for all the products of Block-1 i.e.
Turbo-generators, Hydro-generators, A.C. and D.C.
machines
There are three BAYS in this block each bay
manufactures stator bars and coils for different
machines
5. BAY-I: Bar winding shop: manufacturing of stator winding
bars of generator
BAY-II: Manufacturing of heavy duty generator stator bars
with New CNC M/c
BAY-III: Insulation detail shop: Manufacturing of hard
insulation & machining of hares insulation part (Glass Textolite)
such as packing, washer, insulation box, wedges etc
Bar Shop: This shop is meant for manufacturing of stator
winding coils of turbo-generator and hydro generator
7. Sections in Block IV
1) Assembly Section
It is equipped with small size
• Drilling machines
• Welding sets
• Hydraulic testing equipment
for manufacturing turbo-
generator mechanical
assemblies.
2) Stator Bar Winding Section
It is equipped with
•Conductor cutting, insulation and
transposition section.
•Stack consolidation section,
forming and lug brazing sections.
•Insulation taping sections with
automatic taping facilities in air-
conditioned
3) Impregnation Section
It is equipped with
• Impregnation tank
• Ovens for impregnation of DC pole coils.
8. 4) Armature Winding, Rotor coil and Stator bar Section
It is equipped with
• Conductors cutting.
• U- bending and terminal conductor cutting machines.
• Semi-automatic winding machine.
• Planking, boat pulling and diamond pulling machine.
• Insulation and pressing of AC coils.
5) Insulation Section
It is equipped with
• Small size lathes.
• Milling and radial drilling machines.
• Jet cutting saw.
• Electrical ovens & Hydraulic presses.
•Plastic Molding Section
9. Types of Generators
The generator may be classified based upon the cooling
system used in the generators such as: THRI, TARI, THDI,
THDD, THDF, THFF, and THW
Stands for type
of generator
• T- Turbo
Generator
• H- Hydro
Generator
Stands for the
cooling media
for Rotor
• H- Hydrogen
gas
• A- Air
Stands for the
type of cooling
for Rotor
• R- Radial
• D- Direct
• F- Forced
• I- Indirect
Stands for type
of cooling for
Stator
• I- Indirect
• D- Direct
• F- Forced
Stands for
cooling media
used for Stator
coil
• W- Water
10. It is quite difficult (rather impossible) to manufacture, handle
and wind in the stator slot of generator of higher generation
capacity because of its bigger size and heavy weight. That is
why we make coil in two parts. One part its bottom part of coil
called bottom or lower bar and other part of coil is called top
bar or upper bar.
Why do we call it bar?
12. Poor Resin or Micalastic insulation system
In this type of insulation the bond content in the resin is 5 – 7%
and insulating material is prepared with accelerator treatment.
The temperature control need is not required. The insulating
material is applied on job and then same is impregnated (fully
dipped) in the resin.
Resin System:
Rich Resin or Thermo-reactive insulation system:
In this type of insulation system the bond content in resin is
35 – 37 %. The raw materials are ready to use and require
preservation and working on temperature 20 – 250C. Its shelf
life is one year when kept at a temperature of 200C which
could be increased when kept at temperature of 50C.
13. INSULATION CLASSIFICATION:
Class
Y
• Upto 90 °C
• Cotton, Silk, or Paper.
Class
A
• Upto 105 °C
• Reinforced Class-Y materials with impregnated varnish.
Class
E
• Upto 120 °C
• Cotton lamination & Paper lamination.
Class
B
• Upto 130 °C
• Inorganic material is hardened with adhesives.
Class
F
• Upto 150 °C
• Class-B materials that are upgraded with adhesives.
Class
H
• Upto 180 °C
• Made of inorganic material glued with silicone resin.
Class
C
• > 180 °C Upto 220 °C
• Made of 100% inorganic material
14. Transposition
Transposition means changing/shifting of position of each
conductor in active core (slot) part.
•After cutting the required number of conductors
•The conductors are arranged on the comb in staggered
manner and then bends are given to the conductors with the
help of bending die at required distance.
•Then the conductors are taken out from the comb and die and
placed with their ends in a line and transposition is carried out.
•This process is repeated for making another half of the bar
which would be mirror image of the first half.
•The two halves of the bar are overlapped over each other and
a spacer is placed between the two halves.
15. Need of transposition.
1. To reduce eddy current losses.
2. Equalize the voltage generator.
3. To minimize skin effect of ac current.
Transposition is done in two ways:
Half Pitch Transposition: In this transposition, the first
conductor at one end of the bar becomes the last conductor at
the other end of the bar.
Full Pitch Transposition: In this method of transposition, the
first conductor at one end of the bar becomes the last
conductor in the mid of the bar and then again becomes the
first conductor at the other end of the bar.
16. Testing
Tan δ test:
•This test is carried out to ensure the healthiness of dielectric
(Insulation) i.e. dense or rare & measured the capacitance loss.
•Bar will act as capacitor when it is laid in the stator of the
generator.
•Schearing Bridge which works on the principle of wheat-stone
bridge is used to find the unknown capacitance of the bar.
•For good efficiency, capacitance of the bar should be high but we
never approach pure capacitance.
•Bar is wrapped with aluminum to make the bar conductive
throughout the outer surface of the bar. The two conducting
material i.e. the aluminum sheet and the conductors of the bar act
as two plates of the capacitor and the insulation on the bar act as
dielectric medium for the capacitor thus the capacitance is found.
•Of angle of deviation due to impurity in the insulation is obtained
from the formula: C4 * R4 * 10^-4 = tan δ
17. H.V. Test:
•Each bar is tested momentary at high voltage increased gradually
to three times higher than rated voltage.
•This test is also known as insulation test because this test is
performed to check the insulation of the bar.
•For 600 MW the working voltage of the bar is 64.5 KV & for 210
MW the working voltage of the bar is 63 KV.
•In this test the bar which is already wrapped with aluminum is
used.
•High voltage is applied to the bar using auto-transformer and it is
increased in steps according to the working voltage of the
generator. If the insulation is weak the bar will puncture at the
place of weaker insulation.
•If any of the bar fails this test i.e. bar is punctured at any point
then the bar is sent back for re-insulation and all the processes
are repeated again
18. 2-Pole machine with the following features:
Direct cooling of stator winding with water.
Direct hydrogen cooling for rotor.
Micalastic insulation system.
Spring mounted core housing for effective transmission of
vibrations.
Brushless Excitation system.
Vertical hydrogen coolers
600 MW Turbo generators at a glance
19. Important dimensions & weights:
Heaviest lift of generator stator : 255 Tons
Rotor weight : 68 Tons
Overall stator dimensions [L*B*H] : 8.83m*4.lm*4.02m
Rotor dimensions(Dia. and length) : 1.15m and 12.11m
Total weight of turbo generator : 428 Tons
Salient technical data:
Rated output: 588 MVA , 600 MW
Terminal voltage: 21 KV
Rated stator current: 16 KA
Rated frequency: 50 Hz
Rated power factor: 0.85 Lag
Efficiency: 98.55%