INDUSTRIAL TRAINING REPORTCONTROL AND INSTRUMENTATION NTPC , SHAKTINAGAR ACKNOWLEDGEMENT I convey my gratitude and sincere acknowledgement to Mr NIRMAL SHARMA (AGM, C&I DEPARTMENT) for his kind permission, enabling me to undergo training at C&I LAB. I express my deep sense of gratitude to Mr S.KACHHWAHA (Manager) and Mr A.K.AHMED (Assistant Engineer) for his guidance and kind help extended to me in order to successfully complete my training by providing with adequate information & all required inputs. I would like to thank them for providing me technical knowledge and arranging introductory sessions for innovative and in depth understanding of the working procedures. CONTENTS TOPICS •ABOUT NTPC • ABOUT NTPC SHAKTINAGAR • TECHNICAL SPECIFICATION OF NTPC SHAKTINAGAR •WORKING OF A PLANT •TECHNICAL TERMINOLOGY •MAJOR C&I SYSTEMS i.e. SG & TG packages •FUNCTIONS OF C&I DEPARTMENT •ABOUT MAXDNA SYSTEMS USA •CONCLUSION NTPC is the largest power generating major in the country. NTPC is well on its way to becoming an “Integrated Power Major. NTPC was the first among power utilities in India to start Environment Impact Assessment (EIA) studies and reinforced it with Periodic Environmental Audits. NTPC has remained committed to the environment.ABOUT NTPC POWER GENERATION Presently. . It has also diversified into hydro power. oil & gas exploration. It continues to take various pro-active measures for protection of the environment and ecology around its projects. power trading & distribution. While leading the nation’s power generation league. NTPC generates power from Coal and Gas. coal mining. power equipment manufacturing. With an installed capacity of 31. With an increasing presence in the power value chain.” NTPC has been recently accorded ”MAHARATAN” Status by honourable GOVERNMENT OF INDIA.704 MW. With ambitious growth plans to become a 56000MW power company by 2017.5% of the total equity shares of the company and the balance 10.NTPC is the largest thermal power generating company of India . NTPC the largest power utility of India has already diversified into hydro sector. NTPC today lights up every fourth bulb in the country. NTPC has emerged as a truly national power company. Domestic Banks. At present. Within a span of 30 years. Contributing 26% of the country’s entire power generation. Within a span .A Public sector Company wholly owned by government of India. Government of India holds 89. with power generating facilities in all the major regions of the country. In keeping with its well focused environment protection policy. NTPC has set up a “Centre for Power Efficiency and Environmental protection” (CENPEEP) which functions as a resource centre for development and dissemination of latest technologies in environmental management. It was incorporated in the year 1975 to accelerate power development in the country. 18 NTPC stations have already been accredited with the ISO 14001 certification. Public and others.5% is held by FIIs. of 32 years. with power generating facilities in all the major regions of the country. . NTPC has emerged as a truly national power company. 480 Gas/Liquid Fuel Stations s. 8.600 1. Coal based Singrauli Korba Ramagundam Farakka Vindhyachal Rihand Kahalgaon Dadri Talcher Kaniha Unchahar Talcher Thermal Simhadri Tanda State Uttar Pradesh Chattisgarh Andhra Pradesh West Bengal Madhya Pradesh Uttar Pradesh Bihar Uttar Pradesh Orissa Uttar Pradesh Orissa Andhra Pradesh Uttar Pradesh Commissioned Capacity (MW) 2.100 2.600 3.000 2. 3. 5. 2. 12.Coal Stations S.260@ 2. 7. 18. Gas based Anta Auraiya Kawas Dadri Jhanor-Gandhar Kayamkulam Faridabad Total (Gas) Through Joint Venture State Rajasthan Uttar Pradesh Gujarat Uttar Pradesh Gujarat Kerala Haryana Commissioned Capacity (MW) 413 652 645 817 648 350 430 3. 17.000 440 Total (Coal) @Capacity presently under implementation Vindhyachal 1000 MW Unchahar 210 MW 20. 11. 13. 15.000 840@ 460 1. 10. 4.No 1.000 840@ 840 3.no 14. 6.955 314 . 9. 19. 20. 16. It has secured ISO 14001 and ISO 9002 certificate in the field of environment and power generation but also in various other fields. On November 2009. The station is located in Singrauli district in MP in the north-western side of the country. By next few months. 4260 MW) As a public sector company. it adds 1000 MW more to its capacity (i. NTPC is the sixth largest thermal power generator in the world and the second most efficient utility in terms of capacity utilization based on data of 1998.e.Grand Total (Coal + Gas + JV) 23. it was incorporated in the year 1975 to accelerate power development in the country as a wholly owned company of the Government .749 ABOUT NTPC SHAKTINAGAR Shaktinagar Super Thermal Power station is one of the most prestigious flagships of NTPC striving ahead to bridge the country generation gap especially in the western region. it made glorious achievement by ensuring production up to 3260 MW. with power generating facilities in all the major regions of the country. Domestic Banks. The station is located in Sidhi district in MP in the northwestern side of the country. .of India. The erection work has been completed before scheduled. Government of India holds 89. Work for Stage-III is going on in full swing. On September 2002 it made glorious achievement by ensuring production up to 2260 MW. At present.5% of the total equity shares of the company and the balance 10. NTPC Vindhyachal super thermal power project is one of the most prestigious flagships of NTPC striving ahead to bridge the country generation gap especially in the western region. NTPC has emerged as a truly national power company. By next 06 months it adds 1000MW more to its capacity (3260MW). It has secured ISO 14001 and ISO 9002 certificate in the field of environment and power generation but also in various other fields. Within a span of 31 years.5% is held by FIIs. public and others. TECHNICAL SPECIFICATION ABOUT NTPC VINDHYACHAL TYPE OF STATION STATION CAPACITY 500 STAGE III 2 X 500 STAGE IV 2 X 500 (UNDER CONSTRUCTION) FUEL COAL SOURCE TRANSPORTATION COOLING WATER SOURCE RESERVIOR ASH DISPOSAL RESERVIOR CHIMNEY – FOR 210 MW PLANT – 210m FOR 500 MW PLANT – 265m COAL NIGHAI (NCL) BY RAIL RIHAND RIHAND THERMAL STAGE I 6 x 210 STAGE II 2 X . . Chattisgarh. Gujarat.PLANT AREA - 90-200 ACRES SOURCES FOR RAW MATERIALS COAL SOURCE Northern coalfields limited (NCL) mines at Dudhichua (7Km) and Nigahi (10Km) and Jayant (5Km). WATER SOURCE Discharge canal of Singrauli super thermal power station. Daman & Diu and Dadar & Nagerhaveli. BENEFICIARY STATES Madhya Pradesh. Maharastra. FUEL OIL SOURCE Indian oil corporation (IOC) COLD (customer operated lubricant and oil deposit) at Jayant. regenerative feed water heating and reheating of steam Figure 1A shows this cycle and is self explanatory. It is a closed cycle to enable the working fluid (water) to be used again and again. The cycle used is “Ranking Cycle” modified to include super heating of steam.BASIC POWER PLANT CYCLE The thermal (steam) power plant uses a dual (vapor + liquid) phase cycle. . WORKING OF A THERMAL POWER PLANT COAL TO STEAM Coal from the coal wagons is unloaded in the coal handling plant. where it is ground to a powder form. This table is rotated with the help of a motor.A. Fan (5). There are three large steel rollers which are spaced 120 apart. these rollers does not rotate but when the coal is fed to the table it packs up between roller and the table and this forces the rollers to rotate. The mill consists of a round metallic table on which coal particles fall. Fan taken atmospheric .A. When there is no coal. Coal is crushed by the crushing action between the rollers and rotating table. Coal is transported to Bowl Mills (3) by Coal feeders (2) the coal is pulverized in the Bowl Mill. This crushed coal is taken away to the furnace through coal pipes (4) with the help of hot and cold air mixture from P. P. This Coal is transported up to the raw coal bunkers (1) with the help of belt conveyors. D. Water follows the same path while the steam is sent to super heaters for superheating. Flue gases from the furnace is extracted by induced draft fan (14) which maintains balance draft in the furnace (-5 to -10mm of wcl) with forced draft fan (18). .air. Fan (18) is heated in the air heaters (7) and sent to the furnace (6) as combustion air. Water from the drum passes through down comers and goes to bottom ring header. Water from the boiler feed pump passes through economizer (8) and reaches the boiler drum (9). These flue gases emits their heat . a part of which is sent to Air preheaters (7) for heating while a part goes directly to the mill for temperature control. Water from the bottom ring header is divided to all the four sides of the Furnace. This steam and water mixture is again taken to the boiler drum (9) where the steam is separated from water. Atmospheric air from F. The super heaters are located inside the furnace and the steam is superheated (540°C) and finally it goes to turbine. Due to heat and the density difference the water rises up in the water wall tubes (12). Water is partly converted to steam as it rises up in the furnace. Regular mechanical hammers blows cause the accumulation of ash to fall to the bottom of the precipitator where they are collected in a hopper for disposal. This ash is mixed with water to form slurry and is pumped to ash pond. Electrostatic precipitator consists of metal plates which are electrically charged. so that they do not pass through the chimney (17) to pollute the atmosphere. . Ash particles are attracted on to these plates.energy to various super heaters in the pant house (15) and finally passes through air preheaters (7)and goes to electrostatic precipitator (16) where the ash particles are extracted. STEAM TO MECHANICAL POWER . where it passes through a ring of stationary blades (5) fixed to the cylinder wall (6). driven from the main turbine shaft (4).As can be seen from figure 2. The . Stop valve and control valves are located in a steam chest and a governor (3). On a disc secured to the turbine shaft. from the boiler. operates the control valves to regulate the amount of steam used (This depends upon the speed of the turbine and the amount of electricity required from the generator). Steam from the control valves enters the high pressure cylinder of the turbine. so that the cylinder contains a number of rings of stationary blades with rings of moving blades arranged between them. Ring of moving blades (7) mounted. These act as nozzles and direct the steam into a second. a steam pipe (1) conveys steam to the turbine through a stop valve (which can be used to shut off steam in an emergency) and through control valves (2) that automatically regulate the supply of steam to the turbine. The stationary and moving blades together constitute a ‘stage’ of the turbine and in practice many stages are necessary. This second ring turns the shafts as a result of the force of the steam. 000 revolutions per minute. This speed is determined by the frequency of the electrical system used in this country and is the speed at .an arrangement known as double flow to the extremities of the cylinder. The turbine shaft usually rotates at 3.steam passes through each stage in turn until it reaches the end of the high pressure cylinder and in its passage some of its heat energy is changed into mechanical energy. The steam leaving the high pressure cylinder goes back to the boiler for reheating (8) and returns by a further pipe (9) to the intermediate pressure cylinder. Because of this expansion the blades are much larger and longer towards the low pressure ends of the turbine. its temperature and pressure fall and it expands. Finally. Here it passes through another series of stationary and moving blades. As the steam gives up its heat energy to drive the turbine. the steam is taken to the low pressure cylinders. each of which it enters at the centre (10) flowing outwards in opposite directions through the rows of turbine blades . When as much energy as possible has been extracted from the steam it is exhausted directly to the condenser. This runs the length of the low pressure part of the turbine and may be beneath or on either side of it. From the condenser. This allows the steam to reduce down to pressure below that of the normal atmosphere and more energy can be utilized.000 tubes.which a 2. Cold water from the river. each about 25mm in diameter. after which its pressure is raised to boiler pressure by the boiler feed . a vacuum is created in the condenser. The condenser consists of a large vessel containing some 20.pole generator must be driven to generate alternating current at a frequency of 50 cycles per second. estuary. the condensate is pumped through low pressure heaters by the extraction pump. sea or cooling tower is circulated through these tubes and as the steam from the turbine passes round them it is rapidly condensed into water condensate. Because water has a much smaller comparative volume than steam. 27. it can be returned directly to the source after use. so the cooling water is passed through cooling towers (where its heat is removed by evaporation) and re-used.pump. estuaries or the coast. . about one hundredth part of the cooling water evaporates and a certain amount is returned to its source to carry away any impurities that collect.500 cubic meters pf water an hour for cooling purposes. . Power status situated on smaller rivers and inland do not have such vast water resources available.000 kilowatts (KW) of electricity requires about 2. Most of it however is recirculated.000. A power station generating 2. It is passed through further feed heater to the economizer and the boiler for reconversion into steam. Where cooling towers are used. Where the cooling water for power stations is drawn from large rivers. Firstly.5mm rotating in opposite directions. The pulveriser has a grinder and three rollers at a distance of 2. The coal is . the coal is sent to the bunkers of a RC (Raw Coal) feeder from which it is sent to pulverisers at a controlled rate.The thermal power plant generates electricity using steam which is generated inside boiler by burning coal or oil. The powdered coal (of size less than or equal to 2.5mm) is sent to furnace through pipes. This helps in making hot air in shape of a turbulent like structure which saves the furnace from damage due to uneven heating on any part of furnace.e. excess air required for combustion. The steam from down comer goes to drum which consists of a turbo separator. .fed in through pipes in four directions so as to maintain the temp. inside boiler homogeneous. The drum has an important role as it saves the turbine from water which causes corrosion and thus passes only dry steam. The coal is sent to furnace with the help of PA fans (Primary Air Fans). The igniter ignites the coal which is coming inside the furnace in such a way so that the direction of air through PA fan is tangent to an imaginary circle. The furnace has a goose shaped structure which saves the platen super heater pipes from melting due to direct heat produced from combustion of coal. The furnace walls have water pipes which absorb the heat of combustion and changes water to water vapour. Another fan called FD fan (Forced Draft Fan) is used for secondary air i. The steam and water gets separated out and the water is sent to water walls through risers. The steam is passed through cooled water in tubes where a pressure of 0. This steam. After doing work (rotating turbine) it has a temp. CRH (Cold Reheat) is passed through reheater and then to final superheater and is called HRH (Hot Reheat). Then the steam is passed through LPT (Low Pressure Turbine) with 7. of 540 degree Celsius and a pressure of 38 kg/c m2 and passed through IPT (Intermediate Pressure Turbine).9 atm. of 540 degree Celsius and a pressure of 140-145 kg/cm2.The dry steam is then passed through LTSH (Low Temperature Super Heater) and then to platen super heater for gaining excess heat.5-8 kg/cm2 and 350. All the three turbines have a common shaft which is connected to generator from which electricity is produced. The cooled steam is collected in a large container called hot well decause the water droplets collected is still hot. is being maintained so that the steam flows in a single direction. This steam is sent to HPT (High Pressure Turbine) where it has a temp. This hot water is extracted through CEP (Condensate .370 degree Celsius of temp. of 350 degree Celsius and a pressure of 40 kg/c m2 . The steam now has a temp. respectively. it is passed from deareator where dissolved harmful gases such as sulphur dioxides are removed and then passed to feed water storage tank. The HPH output is connected to economisers and then to drum.Extraction Pump) to drain cooler where it has a temp. of 40 degree Celsius and a pressure of 22 kg/c m2 .LP3 (Low Pressure heaters) with 50. The above cycle repeats for generation of electricity. The BFP’s (Boiler Feed Pump) are used to send this to HPH (High Pressure Heaters) at a pressure of 190-195 kg/cm2. . Now.LP2 . The BFP consists of two parts namely booster pump and main pump. 55 and 60 degree Celsius of temp. This is passed through LP1 . .Figure demonstrating the general outlook of a thermal Power station. Here we use two types of valves:1) Electromotive relief valve 2) Mechanical safety valve Here when the pressure in the furnace is more than the set point then the valve get opened and the steam is released in the atmosphere until the pressure drops to the set point and then the valve gets closed. Then due to more steam more pressure will be generated.TECHNICAL TERMINOLOGY RC FEEDER The function is to decide amount of coal (i. But steam loss is more in mechanical safety valve thus. Considering the case if the amount of coal given to furnace is more than required then as a result due to more heating more steam will be produced.e. powdered coal) to be given in the furnace for heating. . electromotive relief valve is introduced. Load of boiler means the amount of coal which is being burnt in the furnace. If the motor become overloaded we start the coal feed again to make motor load normal. This time is taken is the delay generated known as process delay.BOILER LOAD INDEX It is the index in which load of boiler is indicated. which in these feed the coal at a controlled rate to the pulverisers. Now it takes time to raise the steam pressure after giving the coal to furnace (as it takes some time to produce steam). then to raise the steam pressure to set point we have to give more amount of coal (to produce more steam). FEEDER The crushed raw coal is delivered from the bunkers to the individual. PROCESS DELAY Suddenly when there is pressure drop. . In order to avoid overloading the pulverisation motor due to overfeeding and interrupting circuits should be used to reduce coal feed. desired pressure). LOAD CUTOFF When the load of the boiler is more than the desired then this situation is dangerous. cut-off of load is done for prevention. Now to overcome this condition we use load cut-off which stops the connection of load and boiler i. There 2 types of pressure in consideration:1) Throttle pressure 2) Limit pressure .e.e.So process delay is the delay so as to have the steam pressure being raised to set point when we have to add coal in furnace due to pressure drop. PRESSURE VARIATION When there is a sudden pressure drop we can obviously say that there is pressure variation in the steam pressure from the set point (i. then steam does work and as a result turbine waves and thus rotor moves. Now initially steam does work mechanically and thus rotor moves. Now we consider the case when steam is given to the turbine. RGMO is mostly used instead of FGMO. As a result magnetic field is generated. .GRID BALANCING (Reduction of grid balancing) 1) RGMO – Restricted governing mode of control 2) FGMO – Free governing mode of control Nowadays. Due to thismagnetic field a current is generated and thus electricity is produced. The rotor waves at constant speed. LARGE VIDEO SCREEN (LVS) It is the screen on which various parameters used in the process are displayed with their value. As the process starts from initial state we observe that it rises slowly and reaches to the set or desired point value. ENGINEERING WORK STATION(EWS) It is used by engineers to change/alter the limit or range of any instrument TYPES OF FAN : 1) Forced Draft (FD) Fan: Its function is to enable easy combustion of grounded coal in furnace. It sucks from the atmospheric air which gets heated in the air heaters and then sent to the boiler . . This air is then passed through ESP and finally exhausted through the chimney with the help of ID fans. It operates using three type of air:. 3) Primary Air (PA) Fan: Its function is to blow the crushes coal from ball mill to furnace through pipes. cold air and atmospheric air. 2) Induced Draft (ID) Fan: The air heater receives heat from the boiler and hence the air accompanied there contains a huge amount of ash.hot air.It also supplies hot air to PA Fan if required as per the atmospheric conditions. In this system no water is mixed with ash and the obtained Dry ash is given to cement / brick industries. .ELECTROSTATIC PRECIPITATOR Here fly ash is separated from flue gas and then through ash hammering ash is collected and then passed through a system which is of two types:1) Wet system: . 2) Dry fly ash system: .The dry ash is mixed with water to form slurry and then with ash slurry pump this slurry is sent to ash deck. e. Operation through back up conventional control devices is also possible. SG & TG The SG & TG C&I systems are based on state of the art of the microprocessor technology with CRT/KBD operation facilities. 2. These C&I systems are procured under the respective main plant package i. SG/TG package. flame monitoring. Coal feeder controls 6. Furnace safeguard supervisory system for purging. Control of electromagnetic safety valve . sequential start-up and shut down of mills etc.MAJOR C&I SYSTEMS INCLUDED UNDER MAIN PLANT i. Auxiliary PDRS control system 4. Soot boiler control system 5. THE SG-C&I SYSTEM The SG-C&I system includes the following microprocessor based systems:1. automatic firing. Secondary air damper control system 3.e. all other functional blocks are connected through redundant system bus to achieve integrated CRT/KBD operation & monitoring. Turbine protection system 7. Probes Each of these functional blocks is provided as independent systems which are connected through redundant system bus to achieve integrated CRT/KBD operation & monitoring. HP-LP bypass control system 4. Turbine Supervisory Instruments (TSI) Except for TSI. Automatic Turbine Testing System (ATT) 6. Automatic Turbine Run Up System (ATRS) 3. . Furnace temp. Turbine Stress Control System (TSCS) 5. EHG control system 2. THE TG-C&I SYSTEM The TG-C&I system includes the following functional blocks:1.7. the further measuring. etc and thus helps us to achieve our targets. pumps. The term instrument means “A device or combination of devices used directly or indirectly to measure and display a variable. transmission and control in different technical field. C&I in the same way controls and operates various motors. is a branch in engineering which deals with various measurement. indication. Instrumentation makes use of various measuring components designed to suit the process and the purpose. As some of the big industries and process plant need to control different process variable from a remote distance control room. transmitting.FUNCTIONS OF C&I DEPARTMENT Control and instrumentation in any process industry. C&I. indicating. The way the nerve system controls the operation of various limbs of human beings. innovative. recording and .” Instrumentation is a measurement of various parameters with comparison to set standards. as the name indicates. can be compared to the nerve system in the human being. In industries and process plants. . pressure. control and manipulate electrical as well as non-electrical quantities like temperature. So first these signals are converted into digital signals by “A to D ” convertors. These are combinations of microprocessors and microcontrollers which contain certain logic coding and algorithm which convert analog signals to digital signals. C&I department governs the whole functioning and operation of power plant through the Central Control System (DDC-MIS) “Distributed Digital Control Monitoring and Information System”. vibrations etc.The main work of C&I department is to observe. This is done by the I/O modules. . called Enterprise Management Network. are at the third level. which is accomplished through execution of atomic blocks by DPU in maxDNA. The operator console or the Operator’s Workstation (OWS). to give an open Architecture and reliable control system. The maxDNA DDCMIS follows a multi-level hierarchy. The lowest or first level interacts with the actual plant by acquiring the parameters/status. and the supervisory console or the Engineer’s Workstation (EWS). US.ABOUT MAXDNA SYSTEMS USA The maxDNA Plant Automation System (PAS) is the latest version of Distributed control system developed by Metso Automation MAX Controls. along with high-speed switched Ethernet (maxNET) communications and Distributed Processing Units (DPUs). At the highest level. and issuing the actuating signals/commands. The second level performs closed loop control and open loop control. engineers and managers have access to the entire system database. MaxDNA works with the popular operating systems Microsoft Windows 2000/XP and Windows CE. Provision for user-defined multi-function expandability 4. The attractive features of maxDNA software for the benefit of the engineer or operator are:1. Wide selection of standard library functions 3. User flexibility in assigning inputs/outputs 5. . .MAXDNA software runs on popular Microsoft platforms. Unique address for I/O signals Figure shows network connections of maxDNA systems. High level object-oriented programming in Graphical User Interface(GUI) 2. CONCLUSION I hereby affirm that the information given in this report is true to the best of my knowledge and is based on the training undergone at C&I department . Vidya Sagar and information provided is true to the best of my knowledge and belief.This report fulfils the basic requirement under vocational training for undergraduates. I again affirm that this report is fully made by me. .