REPORT ON :

By:

Ankit RaiB.Tech. in Electronics and Communication

IEC COLLEGE OF ENGINEERING AND TECHNOLOGY

MAHAMAYA TECHNICAL UNIVERSITY

University Roll no. : Student no. :

Contents of Report :

VOCATIONAL TRAINING AT NTPC LTD. BADARPUR THERMAL POWER STATION (BTPS)

1. INTRODUCTION TO THE COMPANY.....................................................................1.1 About the Company....................................................................................1.2 Vision........................................................................................................1.3 Strategies..................................................................................................1.4 Evolution...................................................................................................

2. INTRODUCTION TO THE R MAL POWER PLA N T .....................................................2.1 Introduction...............................................................................................2.2 Classification.............................................................................................2.3 Functioning................................................................................................

1. Operations In NTPC ......................................................................................... 3.1 Introdution................................................................................................3.2 Steam generator or Boiler..........................................................................3.3 Steam Turbine...........................................................................................

3.4 Electric Generator………………………………………………………………………………………………………………………………….

4. Control and Instrumentation Department(C & I)................................................4.1 Manometry Lab..........................................................................................4.2 Protection and Interlock Lab.......................................................................4.3 Automation Lab..........................................................................................4.4 Pyrometer Lab...........................................................................................4.5 Furnace and Supervisory System Lab..........................................................4.6 Electronics Lab...........................................................................................4.7 Annunciatin Cards......................................................................................

5. Information & Technology ( I T ).......................................................................5.1 IT role and responsibility............................................................................5.2 IT applications (BCOMIT)............................................................................5.3 Overview of Online Applications at BTPS.....................................................5.4 Saga of IT Turnaround at BTPS ...................................................................

NTPC Limited

BADARPUR THERMAL POWER STATION

TO WHOM IT MAY CONCERN

I hereby certify that ANKIT RAI Roll No 4586642190 of IEC COLLEGE OF ENGINEERING AND TECHNOLOGY has undergone six weeks Industrial Training from 17th June, 2013 to 24th July, 2013 at our organization to fulfill the requirements for the award of degree of B.Tech in Electronics & Communication Engineering. He works on Power Plant Overview project during the training under the supervision of Mr. Anant K. Varshney, Mrs. Tulika Sharma & Mr. Shyamal Bhattacharya During his tenure with us we found him sincere and hard working. We wish him a great success in the future.

Signature of the Student Signature of the SUPERVISOR (S)

(Seal of Organization)

ACKNOWLEDGEMENT

I am highly grateful to the , Director,IEC college of engineering and technology Greater Noida, for providing this opportunity to carry out the six weeks industrial training at National Thermal Power Corporation, New Delhi.

The constant guidance and encouragement received from Engineers & workers at NTPC has been of great help in carrying out the report work and is acknowledged with reverential thanks.

I would like to express a deep sense of gratitude and thanks profusely to Mr. R. S. Sharma, CMD of the Company, without the wise counsel and able guidance, it would have been impossible to complete the report in this manner.

The help rendered by Ms Rachana Singh Bhal, Supervisor, National Thermal Power Corporation for experimentation is greatly acknowledged.

I expresses gratitude to the HOD and other faculty members of Department of Electronic & Communication Engineering of IEC-CET for their intellectual support throughout the course of this work.

Finally, the authors are indebted to all whosoever have contributed in this report work and friendly stay at Badarpur Thermal Power Station, New Delhi.

ANKIT RAI(HGTYU)

1. Introduction To The C ompany

1.1 About the Company : NTPC, the largest power Company in India, was setup in 1975 to accelerate power development in the country. It is among the world’s largest and most efficient power generation companies. In Forbes list of World’s 2000 Largest Companies for the year 2007, NTPC occupies 411th place.

NTPC has installed capacity of 29,394 MW. It has 15 coal based power stations (23,395 MW), 7 gas based power stations (3,955 MW) and 4 power stations in Joint Ventures (1,794 MW). The company has power generating facilities in all major regions of the country. It plans to be a 75,000 MW company by 2017.

NTPC has gone beyond the thermal power generation. It has diversified into hydro power, coal mining, power equipment manufacturing, oil & gas exploration, powertrading & distribution. NTPC is now in the entire power value chain and is poised to become an Integrated Power Major. NTPC's share on 31 Mar 2008 in the total installed capacity of the country was 19.1% and it contributed 28.50% of the total power generation of the country during 2007-08. NTPC has set new benchmarks for the power industry both in the area of power plant construction and operations.

With its experience and expertise in the power sector, NTPC is extending consultancy services to various organizations in the power business. It provides consultancy in the area of power plant constructions and power generation to companies in India and abroad.In November 2004, NTPC came out with its Initial Public Offering (IPO) consisting of 5.25% as fresh issue and 5.25% as offer for sale by Government of India. NTPC thus became a listed company with Government holding 89.5% of the equity share capital

and rest held by Institutional Investors and Public. The issue was a resounding success. NTPC is among the largest five companies in India in terms of market capitalization.

Recognizing its excellent performance and vast potential, Government of the India has identified NTPC as one of the jewels of Public Sector 'Navratnas'- a potential global giant. Inspired by its glorious past and vibrant present, NTPC is well on its way to realize its vision of being "A world class integrated power major, powering India's growth, with increasing global presence".

1.2 VisionA world class integrated power major, powering India's growth with increasing global presence.

MissionDevelop and provide reliable power related products and services at competitive prices, integrating multiple energy resources with innovative & Eco-friendly technologies and contribution to the society.

Core Values – BCOMIT

• Business ethics • Customer Focus • Organizational & Professional Pride • Mutual Respect & Trust • Innovation & Speed • Total Quality for Excellence

1.3 Strategies

Technological Initiatives

Introduction of steam generators (boilers) of the size of 800 MW Integrated Gasification Combined Cycle (IGCC) Technology Launch of Energy Technology Center -A new initiative for development of

technologies with focus on fundamental R&D The company sets aside up to 0.5% of the profits for R&D Roadmap developed for adopting ‘Clean Development Mechanism’ to help get / earn ‘Certified Emission Reduction

Corporate Social Responsibility

Strategies

Sustainable Development Maintain

sector leadership

position thorough expansion

Further enhance

fuel securityExpoit new

business opportunitiesTechnology

initiative

Technology Initiatives

Nurturing Human

Resource

As a responsible corporate citizen NTPC has taken up number of CSR initiatives NTPC Foundation formed to address Social issues at national level NTPC has framed Corporate Social Responsibility Guidelines committing up to

0.5% of net profit annually for Community Welfare Measures on perennial basis The welfare of project affected persons and the local population around NTPC

projects are taken care of through well drawn Rehabilitation and Resettlement policies

The company has also taken up distributed generation for remote rural areas

Environment Management

All stations of NTPC are ISO:14001 certified Various groups to care of environmental issues The Environment Management Group Ash Utilization Division Afforestation Group Centre for Power Efficiency & Environment Protection Group on Clean Development Mechanism

( NTPC is the second largest owner of trees in the country after the Forest department )

Partnering government in various initiatives

Consultant role to modernize and improvise several plants across the country Disseminate technologies to other players in the sector _ Consultant role

“Partnership in Excellence” Programme for improvement of PLF of 15 Power Stations of SEBs.

Rural Electrification work under Rajiv Gandhi Grameen Vidyutikaran Yojana

1.4 Evolution

NTPC is the largest power utility in India, accounting for about 20% of India’s installed capacity.

2. Introduction To Thermal Power P lant

NTPC was set up in 1975 with 100% ownership by the Government of India. In the last 30

years, NTPC has grown into the largest power utility in India.

In 1997, Government of India granted NTPC status of “Navratna’ being one of the nine

jewels of India, enhancing the powers to the Board of Directors

In 2004, NTPC became a listed company with majority Government ownership of 89.5%.

NTPC becomes third largest by Market Capitalization of listed companies

The company rechristened as NTPC Limited in line with its changing business portfolio and

transforms itself from a thermal power utility to an integrated power utility in 2005.

National Thermal Power Corporation is the largest power generation company in India.

Forbes Global 2000 for 2008 ranked it 411th in the world.

2.1 Introduction

Power Station (also referred to as generating station or power plant) is an industrial facility for the generation of electric power. Power plant is also used to refer to the engine in ships, aircraft and other large vehicles. Some prefer to use the term energy center because it more accurately describes what the plants do, which is the conversion of other forms of energy, like chemicalenergy, gravitational potential energy or heat energy into electrical energy.

However, power plant is the most common term in the U.S., while elsewhere power station and power plant are both widely used, power station prevailing in many Commonwealth countries and especially in the United Kingdom.

At the center of nearly all power stations is a generator, a rotating machine that converts mechanical energy in to electrical energy by creating relative motion between a magnetic field and a conductor. The energy source harnessed to turn the generator varies widely. It depends chiefly on what fuels are easily available and the types of technology that the power company has access to.

In thermal power stations, mechanical power is produced by a heat engine, which transforms thermal energy, often from combustion of a fuel, into rotational energy. Most thermal power stations produce steam, and these are sometimes called steam power stations. About 80% of all electric power is generated by use of steam turbines. Not all thermal energy can be transformed to mechanical power, according to the second law of thermodynamics. Therefore, there is always heat lost to the environment. If this loss is employed as useful heat, for industrial

processes or district heating, the power plant is referred to as a cogeneration power plant or CHP (combined heat-and-power) plant. In countries where district heating is common, there are dedicated heat plants called heat-only boiler stations. An important class of power stations in the Middle East uses byproduct heat for desalination of water.

2.2 Classification

By fuel

Nuclear power plants use a nuclear reactor's heat to operate a steam turbine generator.

Fossil fuelled power plants may also use a steam turbine generator or in the case of natural gas fired plants may use a combustion turbine.

Geothermal power plants use steam extracted from hot underground rocks.

Renewable energy plants may be fuelled by waste from sugar cane, municipal solid waste, landfill methane, or other forms of biomass.

In integrated steel mills, blast furnace exhaust gas is a low-cost, although low-energy density, fuel.

Waste heat from industrial processes is occasionally concentrated enough to use for power generation, usually in a steam boiler and turbine.

By Prime Mover

Steam turbine plants use the dynamic pressure generated by expanding steam to turn the blades of a turbine. Almost all large non-hydro plants use this system.

Gas turbine plants use the dynamic pressure from flowing gases to directly operate the turbine. Natural-gas fuelled turbine plants can start rapidly and so are used to supply "peak" energy during periods of high demand, though at higher cost than base-loaded plants. These may be comparatively small units, and sometimes completely unmanned, being remotely operated. This type was pioneered by the UK, Prince town being the world's first, commissioned in 1959.

Combined cycle plants have both a gas turbine fired by natural gas, and a steam boiler and steam turbine which use the exhaust gas from the gas turbine to produce electricity. This greatly increases the overall efficiency of the plant, and many new base load power plants are combined cycle plants fired by natural gas.

Internal combustion Reciprocating engines are used to provide power for isolated communities and are frequently used for small cogeneration plants. Hospitals, office buildings, industrial plants, and other critical facilities also use them to provide backup power in case of a power outage. These are usually fuelled by diesel oil, heavy oil, natural gas and landfill gas.

Micro turbines, Sterling engine and internal combustion reciprocating engines are low cost solutions for using opportunity fuels, such as landfill gas, digester gas from water treatment plants and waste gas from oil production.

2.3 Functioning

Functioning of thermal power plant:

In a thermal power plant, one of coal, oil or natural gas is used to heat the boiler to convert the water into steam. The steam is used to turn a turbine, which is connected to a generator. When the turbine turns, electricity is generated and given as output by the generator, which is then supplied to the consumers through high-voltage power lines.

Detailed process of power generation in a thermal power plant:

1) Water Intake: Firstly, water is taken into the boiler through a water source. If water is available in a plenty in the region, then the source is an open pond or river. If water is scarce, then it is recycled and the same water is used over and over again.

2) Boiler Heating: The boiler is heated with the help of oil, coal or natural gas. A furnace is used to heat the fuel and supply the heat produced to the boiler. The increase in temperature helps in the transformation of water into steam.

3) Steam Turbine: The steam generated in the boiler is sent through a steam turbine. The turbine has blades that rotate when high velocity steam flows across them. This rotation of turbine blades is used to generate electricity.

4) Generator: A generator is connected to the steam turbine. When the turbine rotates, the generator produces electricity which is then passed on to the power distribution systems.

5) Special mountings: There is some other equipment like the economizer and air pre-heater. An economizer uses the heat from the exhaust gases to heat the feed water. An air pre-heater heats the air sent into the combustion chamber to improve the efficiency of the combustion process.

6) Ash collection system: There is a separate residue and ash collection system in place to collect all the waste materials from the combustion process and to prevent them from escaping into the atmosphere.

*Apart from this, there are various other monitoring systems and instruments in place to keep track of the functioning of all the devices. This prevents any hazards from taking place in the plant.

3. Operations in NTPC

3.1 IntroductionThe operating performance of NTPC has been considerably above the national average. The availability factor for coal stations has increased from 85.03 % in 1997-98 to 90.09 % in 2006-07, which compares favourably with international standards. The PLF has increased from 75.2% in 1997-98 to 89.4% during the year 2006-07 which is the highest since the inception of NTPC.

Operation Room of Power Plant

In Badarpur Thermal Power Station, steam is produced and used to spin a turbine that operates a generator. Water is heated, turns into steam and spins a steam turbine which drives an electrical generator. After it passes through the turbine, the steam is condensed in a condenser; this is known as a Rankine cycle. Shown here is a diagram of a conventional thermal power plant, which uses coal, oil, or natural gas as fuel to boil water to produce the steam. The electricity generated at the plant is sent to consumers through high-voltage power lines.The Badarpur Thermal Power Plant has Steam Turbine-Driven Generators which has a collective capacity of 705MW. The fuel being used is Coal which is supplied from the Jharia Coal Field in Jharkhand. Water supply is given from the Agra Canal.

Table: Capacity of Badarpur Thermal Power Station, New DelhiSr. no. Capacity No. of Generators Total Capacity

1. 210 MW 2 420 MW2. 95 MW 3 285 MW

Total 705 MW

There are basically three main units of a thermal power plant :

Steam Generator or Boiler Steam Turbine Electric Generator

We have discussed about the processes of electrical generation further. A complete detailed description of the three units is given further.

Typical Diagram of a Coal based Thermal Power Plant

Coal is conveyed (14) from an external stack and ground to a very fine powder by large metal spheres in the pulverised fuel mill (16). There it is mixed with preheated air (24) driven by the forced draught fan (20). The hot air-fuel mixture is forced at high pressure into the boiler where it rapidly ignites. Water of a high purity flows vertically up the tube-lined walls of the boiler, where it turns into steam, and is passed to the boiler drum, where steam is separated from any remaining water. The steam passes through a manifold in the roof of the drum into the pendant superheater (19) where its temperature and pressure increase rapidly to around 200 bar and 540°C, sufficient to make the tube walls glow a dull red. The steam is piped to the high pressure turbine (11), the first of a three-stage turbine process. A steam governor valve (10) allows for both manual control of the turbine and automatic set-point following. The steam is exhausted from the high pressure turbine, and reduced in both pressure and temperature, is returned to the boiler reheater (21). The reheated steam is then passed to the intermediate pressure turbine (9), and from there passed directly to the low pressure turbine set (6). The exiting steam, now a little above its boiling point, is brought into thermal contact with cold water (pumped in from the cooling tower) in the condensor (8), where it condenses rapidly back into water, creating near vacuum-like conditions inside the condensor chest. The condensed water is then passed by a feed pump (7) through a deaerator (12), and pre-warmed, first in a feed heater (13) powered by steam drawn from the high pressure set, and then in the economiser (23), before being returned to the boiler drum. The cooling water from the condensor is sprayed inside a cooling tower (1),creating a highly visible plume of water vapor, before being pumped back to the condensor (8) in cooling water cycle. The three turbine sets are sometimes coupled on the same shaft as the three-phase electrical generator (5) which generates an intermediate level voltage (typically 20-25 kV). This is stepped up by the unit transformer (4) to a voltage more suitable for transmission (typically 250-500 kV) and is sent out onto the three-phase transmission system (3). Exhaust gas from the boiler is drawn by the induced draft fan (26) through an electrostatic precipitator (25) and is then vented through the chimney stack (27).

1. Cooling tower 2. Cooling water pump 3. Transmission line (3-phase)

4. Unit transformer (3-phase)

5. Electric generator (3-phase)

6. Low pressure turbine

7. Condensate extraction pump

8. Condensor 9. Intermediate pressure turbine

10. Steam governor valve 11. High pressure turbine 12. Deaerator13. Feed heater 14. Coal conveyor 15. Coal hopper16. Pulverised fuel mill 17. Boiler drum 18. Ash hopper19. Superheater 20. Forced draught fan 21. Reheater22. Air intake 23. Economiser 24. Air preheater25. Precipitator 26. Induced draught fan 27. Chimney Stack

3.2 Steam Generator or Boiler The boiler is a rectangular furnace about 50 ft (15 m) on a side and 130 ft (40 m) tall. Its walls are made of a web of high pressure steel tubes about 2.3 inches (60 mm) in diameter. Pulverized coal is air-blown into the furnace from fuel nozzles at the four corners and it rapidly burns, forming a large fireball at the center. The thermal radiation of the fireball heats the water that circulates through the boiler tubes near the boiler perimeter. The water circulation rate in the boiler is three to four times the throughput and is typically driven by pumps. As the water in the boiler circulates it absorbs heat and changes into steam at 700 °F (370 °C) and 3,200 psi (22.1 MPa). It is separated from the water inside a drum at the top of the furnace. The saturated steam is introduced into superheat pendant tubes that hang in the hottest part of the combustion gases as they exit the furnace. Here the steam is superheated to 1,000 °F (540 °C) to prepare it for the turbine. The steam generating boiler has to produce steam at the high purity, pressure and temperature required for the steam turbine that drives the electrical generator. The generator includes the economizer, the steam drum, the chemical dosing equipment, and the furnace with its steam generating tubes and the superheater coils. Necessary safety valves are located at suitable points to avoid excessive boiler pressure. The air and flue gas path equipment include: forced draft (FD) fan, air preheater (APH), boiler furnace, induced draft (ID) fan, fly ash collectors (electrostatic precipitator or baghouse) and the flue gas stack.

Schematic diagram of a coal-fired power plant steam generator

For units over about 210 MW capacity, redundancy of key components is provided by installing duplicates of the FD fan, APH, fly ash collectors and ID fan with isolating dampers. On some units of about 60 MW, two boilers per unit may instead be provided.

Boiler Furnace and Steam Drum

Once water inside the boiler or steam generator, the process of adding the latent heat of vaporization or enthalpy is underway. The boiler transfers energy to the water by the chemical reaction of burning some type of fuel.The water enters the boiler through a section in the convection pass called the economizer. From the economizer it passes to the steam drum. Once the water enters the steam drum it goes down the down comers to the lower inlet water wall headers. From the inlet headers the water rises through the water walls and is eventually turned into steam due to the heat being generated by the burners located on the front and rear water walls (typically). As the water is turned into steam/vapor in the water walls, the steam/vapor once again enters the steam drum.

External View of an Industrial Boiler at Badarpur Thermal Power Station, New Delhi

The steam/vapor is passed through a series of steam and water separators and thendryers inside the steam drum. The steam separators and dryers remove the water droplets from the steam and the cycle through the water walls is repeated. This process is known as natural circulation.The boiler furnace auxiliary equipment includes coal feed nozzles and igniter guns, soot blowers, water lancing and observation ports (in the furnace walls) for observation of the furnace interior. Furnace explosions due to any accumulation of combustible gases after a tripout are avoided by flushing out such gases from the combustion zone before igniting the coal.The steam drum (as well as the superheater coils and headers) have air vents and drains needed for initial startup. The steam drum has an internal device that removes moisture from the wet steam entering the drum from the steam generating tubes. The dry steam then flows into the superheater coils.Geothermal plants need no boiler since they use naturally occurring steam sources. Heat exchangers may be used where the geothermal steam is very corrosive or contains excessive suspended solids. Nuclear plants also boil water to raise steam, either directly passing the working steam through the reactor or else using an intermediate heat exchanger.

Fuel Preparation SystemIn coal-fired power stations, the raw feed coal from the coal storage area is first crushed into small pieces and then conveyed to the coal feed hoppers at the boilers. The coal is next pulverized into a very fine powder. The pulverizers may be ball mills, rotating drum grinders, or other types of grinders.Some power stations burn fuel oil rather than coal. The oil must kept warm (above its pour point) in the fuel oil storage tanks to prevent the oil from congealing and becoming unpumpable. The oil is usually heated to about 100°C before being pumped through the furnace fuel oil spray nozzles

Boiler Side of the Badarpur Thermal Power Station, New Delhi

Boilers in some power stations use processed natural gas as their main fuel. Other power stations may use processed natural gas as auxiliary fuel in the event that their main fuel supply (coal or oil) is interrupted. In such cases, separate gas burners are provided on the boiler furnaces.

Fuel Firing System and Igniter SystemFrom the pulverized coal bin, coal is blown by hot air through the furnace coal burners at an angle which imparts a swirling motion to the powdered coal to enhance mixing of the coalpowder with the incoming preheated combustion air and thus to enhance the combustion.To provide sufficient combustion temperature in the furnace before igniting the powdered coal, the furnace temperature is raised by first burning some light fuel oil or processed natural gas (by using auxiliary burners and igniters provide for that purpose).

- Air Path

External fans are provided to give sufficient air for combustion. The forced draft fan takes air from the atmosphere and, first warming it in the air preheater for better combustion, injects it via the air nozzles on the furnace wall.The induced draft fan assists the FD fan by drawing out combustible gases from the furnace, maintaining a slightly negative pressure in the furnace to avoid backfiring through any opening. At the furnace outlet, and before the furnace gases are handled by the ID fan, fine dust carried by the outlet gases is removed to avoid atmospheric pollution. This is an environmental limitation prescribed by law, and additionally minimizes erosion of the ID fan.

Auxiliary Systems

- Fly Ash Collection

Fly ash is captured and removed from the flue gas by electrostatic precipitators or fabric bag filters (or sometimes both) located at the outlet of the furnace and before the induced draft fan. The fly ash is periodically removed from the collection hoppers below the precipitators or bag filters. Generally, the fly ash is pneumatically transported to storage silos for subsequent transport by trucks or railroad cars.

- Bottom Ash Collection and Disposal

At the bottom of every boiler, a hopper has been provided for collection of the bottom ash from the bottom of the furnace. This hopper is always filled with water to quench the ash and clinkers falling down from the furnace. Some arrangement is included to crush the clinkers and for conveying the crushed clinkers and bottom ash to a storage site.

- Boiler Make-up Water Treatment Plant and Storage

Since there is continuous withdrawal of steam and continuous return of condensate to the boiler, losses due to blow-down and leakages have to be made up for so as to maintain the desired water level in the boiler steam drum. For this, continuous make-up water is added to the boiler water system. The impurities in the raw water input to the plant generally consist of calcium and magnesium salts which impart hardness to the water. Hardness in the make-up water to the boiler will form deposits on the tube water surfaces which will lead to overheating and failure of the tubes. Thus, the salts have to be removed from the water and that is done by a water demineralising treatment plant (DM).

Ash Handling System at Badarpur Thermal Power Station, New Delhi

A DM plant generally consists of cation, anion and mixed bed exchangers. The final water from this process consists essentially of hydrogen ions and hydroxide ions which is the chemical composition of pure water. The DM water, being very pure, becomes highly corrosive once it absorbs oxygen from the atmosphere because of its very high affinity for oxygen absorption.The capacity of the DM plant is dictated by the type and quantity of salts in the raw water input. However, some storage is essential as the DM plant may be down for

maintenance. For this purpose, a storage tank is installed from which DM water is continuously withdrawn for boiler make-up. The storage tank for DM water is made from materials not affected by corrosive water, such as PVC. The piping and valves are generally of stainless steel. Sometimes, a steam blanketing arrangement or stainless steel doughnut float is provided on top of the water in the tank to avoid contact with atmospheric air. DM water make-up is generally added at the steamspace of the surface condenser (i.e., the vacuum side). This arrangement not only sprays the water but also DM water gets deaerated, with the dissolved gases being removed by the ejector of the condenser itself.

3.3 Steam TurbineSteam turbines are used in all of our major coal fired power stations to drive the generators or alternators, which produce electricity. The turbines themselves are driven by steam generated in 'Boilers' or 'Steam Generators' as they are sometimes called.Energy in the steam after it leaves the boiler is converted into rotational energy as it passes through the turbine. The turbine normally consists of several stages with each stage consisting of a stationary blade (or nozzle) and a rotating blade. Stationary blades convert the potential energy of the steam (temperature and pressure) into kinetic energy (velocity) and direct the flow onto the rotating blades. The rotating blades convert the kinetic energy into forces, caused by pressure drop, which results in the rotation of the turbine shaft. The turbine shaft is connected to a generator, which produces the electrical energy. The rotational speed is 3000 rpm for IndianSystem (50 Hz) systems and 3600 for American (60 Hz) systems.

In a typical larger power stations, the steam turbines are split into three separate stages, the first being the High Pressure (HP), the second the Intermediate Pressure

(IP) and the third the Low Pressure (LP) stage, where high, intermediate and low describe the pressure of the steam. After the steam has passed through the HP stage, it is returned to the boiler to be re-heated to its original temperature although the pressure remains greatly reduced. The reheated steam then passes through the IP stage and finally to the LP stage of the turbine.A distinction is made between "impulse" and "reaction" turbine designs based on the relative pressure drop across the stage. There are two measures for pressure drop, the pressure ratio and the percent reaction. Pressure ratio is the pressure at the stage exit divided by the pressure at the stage entrance. Reaction is the percentage isentropic enthalpy drop across the rotating blade or bucket compared to the total stage enthalpy drop. Some manufacturers utilise percent pressure drop across stage to define reaction.Steam turbines can be configured in many different ways. Several IP or LP stages can be incorporated into the one steam turbine. A single shaft or several shafts coupled together may be used. Either way, the principles are the same for all steam turbines. The configuration is decided by the use to which the steam turbine is put, co-generation or pure electricity production. For cogeneration, the steam pressure is highest when used as process steam and at a lower pressure when used for the secondary function of electricity production.

- Nozzles and Blades

Steam enthalpy is converted into rotational energy as it passes through a turbine stage. A turbine stage consists of a stationary blade (or nozzle) and a rotating blade (or bucket). Stationary blades convert the potential energy of the steam (temperature and pressure) into kinetic energy (velocity) and direct the flow onto the rotating blades. The rotating blades convert the kineti energy into impulse and reaction forces caused by pressure drop, which results in the rotation of the turbine shaft or rotor.Steam turbines are machines which must be designed, manufactured and maintained to high tolerances so that the design power output and availability is obtained. They are subject to a number of damage mechanisms, with two of the most important being:

Erosion due to Moisture: - The presence of water droplets in the last stages of a turbine causes erosion to the blades. This has led to the imposition of an allowable limit of about 12% wetness in the exhaust steam;

Solid Particle Erosion: - The entrainment of erosive materials from the boiler in the steam causes wear to the turbine blades.

- Cogeneration Cycles

In cogeneration cycles, steam is typically generated at a higher temperature and pressure than required for a particular industrial process. The steam is expanded through a turbine to produce electricity and the resulting extractions at the discharge are at the temperature and pressure required by the process. Turbines can be condensing or non-condensing design typically with large mass flows and comparably low output. Traditionally, pressures were 6.21 MPa and below with temperatures 441*C or lower, although the trend towards higher levels of each continues.There are now a considerable number of co-generation steam turbines with initial steam pressures in the 8.63 to 10 MPa range and steam temperatures of 482 to 510*C.

- Bearings and Lubrication

Two types of bearings are used to support and locate the rotors of steam turbines:

Journal bearings are used to support the weight of the turbine rotors. A journal bearing consists of two half-cylinders that enclose the shaft and are internally lined with Babbitt, a metal alloy usually consisting of tin, copper and antimony; and

Thrust bearings axially locate the turbine rotors. A thrust bearing is made up of a series of Babbitt lined pads that run against a locating disk attached to the turbine rotor. High-pressure oil is injected into the bearings to provide lubrication. The oil is carefully filtered to remove solid particles. Specially designed centrifuges remove any water from the oil.

- Shaft Seals

The shaft seal on a turbine rotor consist of a series of ridges and groves around the rotor and its housing which present a long, tortuous path for any steam leaking through the seal. The seal therefore does not prevent the steam from leaking, merely reduces the leakage to a minimum. The leaking steam is collected and returned to a low-pressure part of the steam circuit.

- Turning Gear

Large steam turbines are equipped with "turning gear" to slowly rotate the turbines after they have been shut down and while they are cooling. This evens out the temperature distribution around the turbines and prevents bowing of the rotors.

- Vibration

The balancing of the large rotating steam turbines is a critical component in ensuring the reliable operation of the plant. Most large steam turbines have sensors installed to measure the movement of the shafts in their bearings. This condition monitoring can identify many potential problems and allows the repair of the turbine to be planned before the problems become serious.

3.4 Electric GeneratorThe steam turbine-driven generators have auxiliary systems enabling them to work satisfactorily and safely. The steam turbine generator being rotating equipment

generally has a heavy, large diameter shaft. The shaft therefore requires not only supports but also has to be kept in position

A 95 MW Generator at Badarpur Thermal Power Station, New Delhi

while running. To minimize the frictional resistance to the rotation, the shaft has a number of bearings. The bearing shells, in which the shaft rotates, are lined with a low friction material like Babbitt metal. Oil lubrication is provided to further reduce the friction between shaft and bearing surface and to limit the heat generated.

- Barring Gear (or Turning Gear)

Barring gear is the term used for the mechanism provided for rotation of the turbine generator shaft at a very low speed (about one revolution per minute) after unit stoppages for any reason. Once the unit is "tripped" (i.e., the turbine steam inlet valve is closed), the turbine starts slowing or "coasting down". When it stops completely, there is a tendency for the turbine shaft to deflect or bend if allowed to remain in one position too long. This deflection is because the heat inside the turbine casing tends to concentrate in the top half of the casing, thus making the top half portion of the shaft hotter than the bottom half. The shaft therefore warps or bends by millionths of inches, only detectable by monitoring eccentricity meters.But this small amount of shaft deflection would be enough to cause vibrations and damage the entire steam turbine generator unit when it is restarted. Therefore, the shaft

is not permitted to come to a complete stop by a mechanism known as "turning gear" or "barring gear" that automatically takes over to rotate the unit at a preset low speed. If the unit is shut down for major maintenance, then the barring gear must be kept in service until the temperatures of the casings and bearings are sufficiently low.

Condenser

The surface condenser is a shell and tube heat exchanger in which cooling water is circulated through the tubes. The exhaust steam from the low pressure turbine enters the shell where it is cooled and converted to condensate (water) by flowing over the tubes as shown in the adjacentdiagram. Such condensers use steam ejectors or rotary motor-driven exhausters for continuous removal of air and gases from the steam side to maintain vacuum.

A Typical Water Cooled CondenserFor best efficiency, the temperature in the condenser must be kept as low as practical in order to achieve the lowest possible pressure in the condensing steam. Since the condenser temperature can almost always be kept significantly below 100 oC where the vapor pressure of water is much less than atmospheric pressure, the condenser generally works under vacuum. Thus leaks of noncondensible air into the closed loop must be prevented. Plants operating in hot climates may have to reduce output if their source of condenser cooling water becomes warmer; unfortunately this usually coincides with periods of high electrical demand for air conditioning.The condenser generally uses either circulating cooling water from a cooling tower to reject waste heat to the atmosphere, or once-through water from a river, lake or ocean.

Feedwater Heater

A Rankine cycle with a two-stage steam turbine and a single feedwater heater.

In the case of a conventional steam-electric power plant utilizing a drum boiler, the surface condenser removes the latent heat of vaporization from the steam as it changes states from vapour to liquid. The heat content (btu) in the steam is referred to as Enthalpy. The condensate pump then pumps the condensate water through a feedwater heater. The feedwater heating equipment then raises the temperature of the water by utilizing extraction steam from various stages of the turbine.

A Rankine cycle with a two-stage steam turbine and a single feedwater heater

Preheating the feedwater reduces the irreversibilities involved in steam generation and therefore improves the thermodynamic efficiency of the system.[9] This reduces plant operating costs and also helps to avoid thermal shock to the boiler metal when the feedwater is introduced back into the steam cycle.

- Superheater

As the steam is conditioned by the drying equipment inside the drum, it is piped from the upper drum area into an elaborate set up of tubing in different areas of the boiler.

The areas known as superheater and reheater. The steam vapor picks up energy and its temperature is now superheated above the saturation temperature. The superheated steam is then piped through the main steam lines to the valves of the high pressure turbine.

- Deaerator

A steam generating boiler requires that the boiler feed water should be devoid of air and other dissolved gases, particularly corrosive ones, in order to avoid corrosion of the metal.Generally, power stations use a deaerator to provide for the removal of air and other dissolved gases from the boiler feedwater. A deaerator typically includes a vertical, domed deaeration section mounted on top of a horizontal cylindrical vessel which serves as the deaerated boiler feedwater storage tank.

Boiler Feed Water Deaerator (with vertical, domed aeration section and horizontal water storage section)

There are many different designs for a deaerator and the designs will vary from onemanufacturer to another. The adjacent diagram depicts a typical conventional trayed deaerator. If operated properly, most deaerator manufacturers will guarantee that oxygen in the deaerated water will not exceed 7 ppb by weight (0.005 cm3/L).

Auxiliary Systems- Oil System

An auxiliary oil system pump is used to supply oil at the start-up of the steam turbine generator. It supplies the hydraulic oil system required for steam turbine's main inlet steam stop valve, the governing control valves, the bearing and seal oil systems, the relevant hydraulic relays andother mechanisms.At a preset speed of the turbine during start-ups, a pump driven by the turbine main shaft takes over the functions of the auxiliary system.

- Generator Heat Dissipation

The electricity generator requires cooling to dissipate the heat that it generates. While small units may be cooled by air drawn through filters at the inlet, larger units generally require special cooling arrangements. Hydrogen gas cooling, in an oil-sealed casing, is used because it has the highest known heat transfer coefficient of any gas and for its low viscosity which reduces windage losses. This system requires special handling during start-up, with air in the chamber first displaced by carbon dioxide before filling with hydrogen. This ensures that the highly flammable hydrogen does not mix with oxygen in the air. The hydrogen pressure inside the casing is maintained slightly higher than atmospheric pressureto avoid outside air ingress. The hydrogen must be sealed against outward leakage where the shaft emerges from the casing. Mechanical seals around the shaft are installed with a very small annular gap to avoid rubbing between the shaft and the seals. Seal oil is used to prevent the hydrogen gas leakage to atmosphere. The generator also uses water cooling. Since the generator coils are at a potential of about 15.75 kV and water is conductive, an insulating barrier such as Teflon is used to interconnect the waterline and the generator high voltage windings. Demineralized water of low conductivity is used.

- Generator High Voltage System

The generator voltage ranges from 10.5 kV in smaller units to 15.75 kV in larger units. The generator high voltage leads are normally large aluminum channels because of their high current as compared to the cables used in smaller machines. They are enclosed in well-grounded aluminum bus ducts and are supported on suitable insulators. The generator high voltagechannels are connected to step-up transformers for connecting to a high voltage electrical substation (of the order of 220 kV) for further transmission by the local power grid.The necessary protection and metering devices are included for the high voltage leads. Thus, the steam turbine generator and the transformer form one unit. In smaller units, generating at 10.5 kV, a breaker is provided to connect it to a common 10.5 kV bus system.

Other Systems

- Monitoring and Alarm system

Most of the power plant’s operational controls are automatic. However, at times, manual intervention may be required. Thus, the plant is provided with monitors and alarm systems that alert the plant operators when certain operating parameters are seriously deviating from their normal range.

An Engineer monitoring the various parameters at NTPC, New Delhi

- Battery Supplied Emergency Lighting & Communication

A central battery system consisting of lead acid cell units is provided to supply emergency electric power, when needed, to essential items such as the power plant's control systems, communication systems, turbine lube oil pumps, and emergency lighting. This is essential for a safe, damage-free shutdown of the units in an emergency situation.

4. Control and Instrumentation Department(C & I)

This department is the brain of the plant because from the relays to transmitters followed by the electronic computation chipsets and recorders and lastly the controlling circuitry, all fall under this.

Measuring Instruments

In any process the philosophy of instrumentation should provide a comprehensive intelligence feedback on the important parameters viz. Temperature, Pressure, Level and Flow. This Chapter Seeks to provide a basic understanding of the prevalent instruments used for measuring the above parameters.

T emperature Measurement

The most important parameter in thermal power plant is temperature and its measurement plays a vital role in safe operation of the plant. Rise of temperature in a substance is due to the resultant increase in molecular activity of the substance on application of heat; which increases the internal energy of the material. Therefore there exists some property of the substance, which changes with its energy content. The change may be observed with substance itself or in a subsidiary system in thermodynamic equilibrium, which is called testing body and the system itself is called the hot body. Expansion Thermometer Solid Rod Thermometers a temperature sensing - controlling device may be designed incorporating in its construction the principle that some metals expand more than others for the same temperature range. Such a device is the thermostat used with water heaters

The mercury will occupy a greater fraction of the volume of the container than it will at a low temperature. Under normal atmospheric conditions mercury normally boils at a temperature of (347°C). To extend the range of mercury in glass thermometer beyond this point the top end of a thermometer bore opens into a bulb which is many times larger in capacity than the bore. This bulb plus the bore above the mercury, is then filled with nitrogen or carbon dioxide gas at a sufficiently high pressure to prevent boiling at the highest temperature to which the thermometer may be used. Mercury in Steel the range of liquid in glass thermometers although quite large, does not lend itself to all industrial practices. This fact is obvious by the delicate nature of glass also the position of the measuring element is not always the best position to read the result.

Types of Hg in Steel Thermometers are:

Bourdon Tube most common and simplest type

Spiral type more sensitive and used where compactness is necessary

Helical Type Most sensitive and compact.

Pressure Measurement

Dewrance Critical Pressure Gauge Measurement of Level Direct Methods 'Sight Glass' is used for local indication on closed or open vessels. A sight glass is a tube of toughened glass connected at both ends through packed unions and vessel. The liquid level will be the same as that in the vessel. Valves are provided for isolation and blow down. "Float with Gauge Post" is normally used to local indication on closed or open vessels. "Float Operated Dial" is used for small tanks and congested areas. The float arm is connected to a quadrant and pinion which rotates the pointer over a scale.

Bourden Pressure Gauge a Bourdon pressure gauge calibrated in any fact head is often connected to a tank at or near the datum level. "Mercury Manometer" is used for remote indication of liquid level. The working principle is the same as that of a manometer one limp of a U-tube is connected to the tank, the other being open to atmosphere. The manometer liquid must not mix with the liquid in the vessel, and where the manometer is at a different level to the vessel, the static head must be allowed in the design of the manometer. 'Diaphragm Type' is used for remote level indication in open tanks or docks etc. A pressure change created by the movement of a diaphragm is proportional to a change in liquid level above the diaphragm. This consists of a cylindrical box with a rubber or plastic diaphragm across its open end as the level increases .the liquid pressure on the diaphragm increases and the air inside is compressed. This pressure is transmitted via a capillary tube to an indicator or recorder incorporating a pressure Measuring element. Sealed Capsule Type The application and principle is the same as for the diaphragm box. In this type, a capsule filled with an inert gas under a slight pressure is exposed to the pressure due to the head of liquid and is connected by a capillary to an indicator. In some cases the capsule is fitted external to the tank and is so arranged that it can be removed whilst the tank is still full, a spring loaded valve automatically shutting off the tapping point. Air Purge System This system provides the simplest means of obtaining an indication of level, or volume, at a reasonable distance and above or below, the liquid being measured. The pressure exerted inside an open ended tube below the surface of a liquid is proportional to the depth of the liquid

Flow Measurement

The Measurement of Flow Two principle measurements are made by flow meters viz. quantity of flow and rate of flow. 'Quantity of flow' is the quantity of fluid passing a given point in a given time, i.e. gallons or pounds. ‘Rate of flow' is the speed of. a fluid passing

a given point at a given instant and is proportional to quantity passing at a given instant, i.e. gallons per minute or pounds per hour. There are two groups of measuring devices: - Positive, or volumetric, which measure flow by transferring a measured quantity of fluid from the inlet to the outlet. Inferential, which measures the velocity of the flow and the volume passed is inferred, it being equal to the velocity times the cross sectional area of the flow. The inferential type is the most widely used. Measurement of Fluid Flow through Pipes: "The Rotating Impeller Type" is a positive type device which is used for medium quantity flow measurement i.e., petroleum and other commercial liquids. It consists of Two fluted rotors mounted in a liquid tight case fluid flow and transmitted to a counter. Rotating Oscillating Piston Type This is also a positive type device and is used for measuring low and medium quantity flows, e.g. domestic water supplies. This consists of a brass meter body into which is fitted a machined brass working chamber and cover, containing a piston made of ebonite. This piston acts as a moving chamber and transfers a definite volume of fluid from the inlet to the outlet for each cycle. Helical Vane Type For larger rates of flow, a helical vane is mounted centrally in the body of the meter. The helix chamber may be vertical or horizontal and is geared to a counter. Usually of pipe sizes 3" to 10" Typical example is the Kent Torrent Meter. Turbine Type this like the helical Vane type is a inference type of device used for large flows with the minimum of pressure drop. This consists of a turbine or drum revolving in upright bearings, retaining at the top by a collar. Water enters the drum from the top and leaves tangentially casings to rotate at a speed dependent upon the quantity of water passed. The cross sectional area of the meter throughout is equal to the area of the inlet and outlet pipes and is commonly used on direct supply water mains, Combination Meters this is used for widely fluctuating flows. It consists of a larger meter (helical, turbine or fan) in the main with a small rotary meter or suitable type in a bypass. Flow is directed into either the main or bypass according to the quantity of flow by an automatic valve. By this means flows of 45 to 40,000 gallons per hour can be measured. Measurement of Fluid Flow through Open Channels: The Weir If a fluid is allowed to flow over a square weir of notch, The height of the liquid above the still of the weir, or the bottom of the notch will be a measure of the rate of flow.

A formula relates the rate of flow to the height and is dependent upon the design of the Venturi Flumes The head loss caused by the weir flow meter is considerable and its construction is sometimes complicated, therefore the flume is sometimes used. The principle is same as that of venture except that the rate of flow is proportional to the depth of the liquid in the upstream section. It consists of a local contraction in the cross section of flow through a channel in the shape of a venturi. It is only necessary to measure the depth of the upstream section which is a measure of the rate of flow. This may be done by pressure tapping at the datum point or by a float in an adjacent level chamber. Pressure Difference Flow meters These are the most widely used type of flow meter since they are capable of measuring the flow of all industrial fluids passing

through pipes. They consists of a primary element inserted in the pipeline which generates a differential pressure, ^he magnitude of which is proportional to the square of the rate of flow and a secondary element which measures this differential pressure and translates it into terms of flow

Primary elements Bernoulli's theorem states that the quantity of fluid or gas flowing is proportional to the square root of the differential pressure. There are four principal types of primary elements (or restrictions) as enumerate below: Venturi; This is generally used for medium and high quantity fluid flow and it consists of two hollow truncated cones, the smaller diameters of which are connected together by a short length of parallel pipe, the smallest diameter of the tube formed by this length of parallel pipe is known as the throat section and the lower of the two pressures, (the throat, or downstream pressure) is measured here. Orifice Plate This is the oldest and most common form of pressure differential device. In its simplest form it consists of a thin metal plate with a central hold clamped between two pipe flanges. In the metering of dirty fluids or fluids containing solids the hole is placed so that its lower edge coincides with the inside bottom of the pipe. It is essential that the leading edge of the hole is absolutely sharp rounding or burring would have a very marked effect on the flow

4.1 Manometry Lab

TRANSMITTER

It is used for pressure measurements of gases and liquids, its working principle is that the input pressure is converted into electrostatic capacitance and from there it is conditioned and amplified. It gives an output of 4-20 ma DC. It can be mounted on a pipe or a wall. For liquid or steam measurement transmitters is mounted below main process piping and for gas measurement transmitter is placed above pipe.

MANOMETER

It’s a tube which is bent, in U shape. It is filled with a liquid. This device corresponds to a difference in pressure across the two limbs.

BOURDEN PRESSURE GAUGE

It’s an oval section tube. Its one end is fixed. It is provided with a pointer to indicate the pressure on a calibrated scale. It is of 2 types:

(a) Spiral type: for Low pressure measurement.

(b) Helical Type: for High pressure measurement

4.2 Protection and Interlock Lab

INTERLOCKING

It is basically interconnecting two or more equipments so that if one equipments fails other one can perform the tasks. This type of interdependence is also created so that equipments connected together are started and shut down in the specific sequence to avoid damage. For protection of equipments tripping are provided for all the equipments. Tripping can be considered as the series of instructions connected through OR GATE. When a fault occurs and any one of the tripping is satisfied a signal is sent to the relay, which trips the circuit. The main equipments of this lab are relay and circuit breakers. Some of the instrument uses for protection are:

1. RELAY : It is a protective device. It can detect wrong condition in electrical circuits by constantly measuring the electrical quantities flowing under normal and faulty conditions. Some of the electrical quantities are voltage, current, phase angle and velocity.

2. FUSES : It is a short piece of metal inserted in the circuit, which melts when heavy current flows through it and thus breaks the circuit. Usually silver is used as a fuse material because: a) The coefficient of expansion of silver is very small. As a result no critical fatigue occurs and thus the continuous full capacity normal current ratings are assured for the long time. b) The conductivity of the silver is unimpaired by the surges of the current that produces temperatures just near the melting point. c) Silver fusible elements can be raised from normal operating temperature to vaporization quicker than any other material because of its comparatively low specific heat.

MINIATURE CIRCUIT BREAKER

They are used with combination of the control circuits to:

a) Enable the staring of plant and distributors.

b) Protect the circuit in case of a fault. In consists of current carrying contacts, one movable and other fixed.

When a fault occurs the contacts separate and are is stuck between them. There are three types of - MANUAL TRIP - THERMAL TRIP - SHORT CIRCUIT TRIP

P ROTECTION AND INTERLOCK SYSTEM

a) H igh Tension control Circuit

For high tension system the control system are excited by separate D.C supply. For starting the circuit conditions should be in series with the starting coil of the equipment to energize it. Because if even a single condition is not true then system will not start.

b) Low Tension control Circuit

For low tension system the control circuits are directly excited from the 0.415 KV A.C supply. The same circuit achieves both excitation and tripping. Hence the tripping coil is provided for emergency tripping if the interconnection fails.

4.3 Automation LabThis lab deals in automating the existing equipment and feeding routes. Earlier, the old technology dealt with only (DAS) Data Acquisition System and came to be known as primary systems. The modern technology or the secondary systems are coupled with (MIS) Management Information System. But this lab universally applies the pressure measuring instruments as the controlling force. However, the relays are also provided

but they are used only for protection and interlocks. Once the measured is common i.e. pressure the control circuits can easily be designed with single chips having multiple applications. Another point is the universality of the supply, the laws of electronic state that it can be any where between 12V and 35V in the plant. All the control instruments are excited by 24V supply (4-20mA) because voltage can be mathematically handled with ease therefore all control systems use voltage system for computation. The latest technology is the use of ‘ETHERNET’ for control signals.

4.4 Pyrometer LabLIQUID IN GLASS THERMOMETER

Mercury in the glass thermometer boils at 340 degree Celsius which limits the range of temperature that can be measured. It is L shaped thermometer which is designed to reach all inaccessible places.

ULTRA VIOLET CENSOR

This device is used in furnace and it measures the intensity of ultra violet rays there and according to the wave generated which directly indicates the temperature in the furnace.

THERMOCOUPLES

This device is based on SEEBACK and PELTIER effect. It comprises of two junctions at different temperature. Then the emf is induced in the circuit due to the flow of electrons. This is an important part in the plant.

RTD (RESISTANCE TEMPERATURE DETECTOR )

It performs the function of thermocouple basically but the difference is of a resistance. In this due to the change in the resistance the temperature difference is measured. In this lab, also the measuring devices can be calibrated in the oil bath or just boiling water (for low range devices) and in small furnace (for high range devices).

4.5 Furnace and Supervisory System Lab

This lab has the responsibility of starting fire in the furnace to enable the burning of coal. For first stage coal burners are in the front and rear of the furnace and for the second and third stage corner firing is employed. Unburnt coal is removed using forced draft or induced draft fan. The temperature inside the boiler is 1100 degree Celsius and its

height is 18 to 40 m. It is made up of mild steel. An ultra violet sensor is employed in furnace to measure the intensity of ultra violet rays inside the furnace and according to it a signal in the same order of same mV is generated which directly indicates the temperature of the furnace. For firing the furnace a 10 KV spark plug is operated for ten seconds over a spray of diesel fuel and pre-heater air along each of the feeder-mills. The furnace has six feeder mills each separated by warm air pipes fed from forced draft fans. In first stage indirect firing is employed that is feeder mills are not fed directly from coal but are fed from three feeders but are fed from pulverized coalbunkers. The furnace can operate on the minimum feed from three feeders but under not circumstances should any one be left out under operation, to prevent creation of pressure different with in the furnace, which threatens to blast it.

4.6 Electronics LabThis lab undertakes the calibration and testing of various cards. It houses various types of analytical instruments like oscilloscopes, integrated circuits, cards auto analyzers etc. Various processes undertaken in this lab are:

1. Transmitter converts mV to mA

2. Auto analyzer purifies the sample before it is sent to electrodes. It extracts the magnetic portion.

4.7 Annunciatin CardsThey are used to keep any parameter like temperature etc. within limits. It gets a signal if parameter goes beyond limit. It has a switching transistor connected to relay that helps in alerting the UCB.

5. Information and Technology ( I T )Integrated IT Enablement of Business Processes for efficient plant

management.

Information Any time, Any where.

5.1 IT Role & Responsibility Development, Implementation & Support for Local Applications

Procurement & Maintenance of IT Infrastructure ( PCs, Printers, Servers & Network LAN,WAN etc)

Support to users for ERP & modules to supplement ERP. Customization & Implementation support for BTPS Applications to other

projects.

5.2 I T Applications (BCOMIT) Power Generation is a complex business. It involves operation and maintenance of more than 15,000 equipments. There are about 40,000 different materials and spares required for smooth operation of power plant apart from coal which is a major raw material, apart from Human Resources & Finance. In today’s, competitive environment, it is important to maintain high availability of the Power Plant at lower cost to survive and maintain profitability.

At BTPS, Information Technology has been used extensively for effective management of various business processes and resources.

Major Innovation in this direction has been, in house Development & Implementation of an Integrated Suite of Online Applications BCOMIT on Oracle database , to manage following business processes;

1 Maintenance Management System 2 Materials Management System3 Financial Accounting System.4 Contracts Management System5 Operations & ABT Monitoring System6 Coal Monitoring & Accounting System.7 Hospital Management System 8 HR, T/S & Training Management System 9 Office Automation & Communication System10 E-Samadhan complaints monitoring system

Some of the above applications replaced by ERP.

BCOMIT@BTPS Provides Online up to minute information and transaction ability, of all business processes, for efficient power plant management. It provides for Effective management of basic resources, i.e. Men, Machines, Materials & Money.

BTPS Applications BCOMIT Highlights

1 Single Login screen for all systems.2 Pass Word & Role based secured access. 3 G.U. Interface, Easy information retrieval & search facility.4 Information captured once at source. 5 Automation of routine activities. 6 Cost effective I T Infrastructure.7 Rapid response & change capability.8 Empowering People with decision support system.

Benefits of IT Innovations @ BTPS

1. Operations Important & critical parameters of Power Plant operation are monitored online to enable effective control on operation of various equipments and reduce down time. Online load analysis & Generation values are monitored to have optimum load balance of various units. Auxiliary power consumption monitored and controlled. Meritorial operation practicing enabled.

2. Maintenance Better control over maintenance cost by way of online information available through the system.Based on failure analysis and equipment history, modified maintenance strategy of Preventive, Predictive and Risk Based maintenance is implemented. Equipment spares planning are streamlined by way of Annual requirement, Vendor wise, linked to Equipment. Standardization of defects and repair codes for easy filling of Work Order Card, for future analysis.

3. Materials Material Planning and Procurement system streamlined, resulting in reduction in Administrative lead Time. Further, procurement on Annual Rate Contract basis enabled through the system. Ordering on actual need basis (just in time). This further reduces lead time and Inventory carrying.

Detection of duplicate and obsolete items, standardization of material description and specification. Cleaning and Weeding of redundant data, resulting in overall system improvement and functionalities. Availability of coal stock status online,

reduction in demurrages paid to railways.

4. Office Automation and Communication

With implementation of e-Desk/e-broadcast, e-alerts, auto mail and BTPS website, information is available instantly to all and all time, resulting in tremendous reduction in paper communication and cost.

Concept to Implementation of IT Innovations @ BTPS

1. IT Infrastructure selection : After detail analysis and survey, Oracle 9i RDBMS on Intel Unix Platform with IDS as front end development tool was chosen, as it is latest and cost effective technology.

2. Application Development : Design and development of New Applications, was taken up in house. This involved understanding various business processes, interaction with user groups of various department, defining computerization needs, development and trial of the applications, considering company policies and procedures.

3. Procurement of Hardware & Software : Intel LAN Server with Oracle 9i RDBMS software and Pentium IV Computers were procured and deployed in various departments of BTPS to provide appropriate IT Infrastructure. All PCs were connected in Plant wide Local area Network using cost effective technology.

4. Implementation of Applications : Various Online Applications as mentioned above were developed tested and implemented in phased manner over a period of time. Any innovation involves major change over and disturbance during transition phase. This was managed with support of management, commitment and expertise of IT team and cooperation of users.

5. Training : For effective implementation and utilization of new IT Applications, major thrust was given on training and retraining. Everybody from Operator to General Manager was covered. Young Computer Professionals were deployed for short

period to provide on the table training to users on need basis to supplement IT department efforts.

6. Data Migration : Data Migration from old legacy systems of various departments was a major exercise for effective implementation of new systems. Old historical data is valuable for reporting, analysis and decision support system. It was handled effectively by IT team in association with users.

5.3 Overview of Online Applications at BTPS

Maintenance Management system, Anurakshan @ BTPS

1 Work Order Card registration for PM, BD & OH.2 Permit to Work Issue, Closure of WOC with detailed feedback.3 Daily Plant Meeting and CHP Meeting minutes generated online.4 Trends of defects priority wise /department wise for a period.5 Equipment history with detailed WOC feedback available.6 Analysis of repeated equipment failure for corrective action.7 Standardization of defects & repair codes.8 Interface with Materials Management System & CMS for WOC cost.

ABT & Operation Performance Monitoring System

(With Frequency trend analysis)

Materials & Contract Management System (CMS)

1 Initiation and approval of Contract Proposal.2 Preparation of Tender Documents and approvals.3 Bids Evaluation and preparation of CS.4 Issue of LOI, LOA and Approvals.5 Preparation of MB and processing of Bills.

FINANANCIAL ACCOUNTING SYSTEM (FAS)

1 Proactive Payroll Process. Transactions effect visible in provisional pay slip.

2 Status of Income Tax Details, PF slip, Leave, Accrued Interest, Earning Card available online.

3 Fund Flow Statements & other Reports for day to day functioning. 4 Bank Reconciliation.5 Automatic maintenance of Trial Balance, GL, Sub ledgers and schedules from

vouchers.

Coal Accounting System (CAS)

1 Online uploading of Wagon wise Weight from Wagon Tipplers.2 Linkage of Coal Bills to GRS Weight.3 Coal and Rail Freight bill payments accounting & reconciliation.4 Tariff Summary, coal accounting and MIS reports generated from the system.

REWARDS & RECOGNITION

Badarpur has achieved unique distinction of being, First site in NTPC, with independent initiative of Development & Implementation of new Oracle based integrated online Applications, with in house effort. This has been appreciated by NTPC higher management.

BTPS Received Golden Peacock award for IT Innovation in 2004.

Adoption of Best Practices : BTPS IT strives to provide value added services and features thru best practices, to support management initiatives & users requirement.

Conclusion :

The BTPS IT has come a long way to leading position in IT enablement among NTPC power stations. IT Vision realized, making BTPS highly Information enabled Plant.

Success Factor :

In house development using latest technology, effective change management, training & using synergized force of People of BTPS (Management, IT Team & Users).

5.4 Saga of IT Turnaround at BTPS

Realization of IT vision of making BTPS highly IT enabled Plant with Online up to date information and transaction ability.

Cost effective I T Infrastructure. Adopting latest technology & skills. Developed by dedicated & motivated IT Team in house. Continuous learning thru training, workshops, Internet. Continuous improvements thru user feedback & Innovations. On the Desk User training from operator to senior executives. IT Evolution as People’s Movement. Synergized force of BTPS (Management, IT Team & Users ). Effective Change Management. User friendly Applications & Services. Achieving User satisfaction & affection.