Post on 25-Jun-2015
description
VOCATIONAL TRAINING PRESENTATION2014 - 15
NAME : LAKHAMAN B. VADHER
DEPTT : ELECTRICAL
COLLEGE : GOVERNMENT ENGNEERING COLLEGE BHARUCH
Introduction
• In India 70% of total power is generated by the Thermal Power Stations.
• Essar power is one leading company in electrical power generation
• Essar Power Salaya
• Capacity:- 1200 MW (2*600 MW)• It is based on coal fired power plant• Project site area :- 330 Ha• Narmada water used as condenser cooling water Boiler
water• Power evacuation at 400 KV to state utility
Major Learning
• Boiler Unit • TG (Turbine Generator) Unit• Transformer Yard• Switchyard(HV,MV,LV)• Coal Handling System• Ash Handling System• ESP (Electrostatic Precipitator)• Cooling Tower• Different type of Motor and Pump•
Basic Layout of Thermal Power Plant
Boiler
• Boiler is steam generator. It convert water into high pressure and high temperature steam
• In Essar power plant Salaya Subcritical type of boiler is used.
• A subcritical steam generator is a type of boiler that operates at subcritical pressure
• Main steam flow:- 2060 TPH• Main steam outlet pres.:- 17.50 Mpa• Main steam outlet temp.:- 541°C• Feed water pres.:- 19.492 Mpa• Feed water temp. :- 281.7 °C• Reheat steam flow :- 1725.9 TPH
6
Schematic Diagram of subcritical Boiler
BOILER SIDEVIEW
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Steam Turbine
• A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft
• And main output shaft is coupled with electrical generator• Turbine divided into 3 Stage
I. HP (High Pressure Turbine)II. IP (Intermit Pressure Turbine)III. LP (Low Pressure Turbine)
• Rated Output :- 600 MW• Rated Speed :- 3000 RPM• Steam pressure :- 16.7 Mpa• Steam temperature :- 538 °C• Direction of rotation :- Clockwise
Steam Turbine
Electrical Generator
• Electric generator is a device that converts mechanical energy to electrical energy.
• Main part of generator are stator and rotor.• Output of electrical power taken from stator terminal.• D.C. supply to the rotor winding through brush and slip
ring.• In Essar power water hydrogen cool synchronous
generator is used
Generator
Generator Specification
Parameter Value
MW Rating 600MW
Rated Voltage 20KV
Rated Stator current 20377 A
Rated Speed 3000 RPM
Rated Frequency 50 Hz
Generator Cooling
• Cooling needed in large size generator Two Type of Cooling system
I.Water cooling II.Hydrogen cooling
• Water is used for stator cooling.• Hydrogen are used for rotor cooling as well as stator
cooling
STATOR COOLING
WATER TANK
STATOR COOLING
WATER TANK
MM
MM
COOLER A
COOLER A
COOLER B
COOLER B
STATOR COOLING WATER PUMP A
STATOR COOLING WATER PUMP B
GENERATORGENERATOR
STRAINER B
STRAINER A
Stator water cooling cycle
Transformer Yard
Main Equipment used Trafoyard
I. GCB (Generator Circuit Breaker)II. ST (Station Transformer)III. UT (Unit Transformer)IV. GT (Generator Transformer)V. NGR (Neutral Grounding Resistor)
Transformer Yard SLD
GCB
• Protection of the Generator against system-fed shortcircuit currents
• The GCB is an effective protection device for the transformer and the generator
I. Starting and maintenance stages
II. Synchronization and normal conditions
III. Abnormal conditions including• Overvoltages, un-balanced load•
Short circuit–
Step up transformer side–
Generator side•
Out of Phase Requirements
Station Transformer
• ST is used supply station common load such as Coal handling,DM plant, etc.
• Transformer used in salaya power plant is three winding transformer
• Specification
Parameter Value
Rated MVA 70 MVA
Voltage 20/11/33KV
Frequency 50Hz
Number Phase 3
Vector Group Dyn11yn11
Unit Transformer
• Unit Transformer supply separate unit load such as Boiler auxiliary,Cooling tower and Turbine auxiliary etc.
• Specification
Parameter Value
Rated MVA 45MVA
Rated Voltage 20/11.5KV
No. Of Phase 3
Vector Group Dy11
GT(Generator Transformer)
• As an essential element of all nuclear, thermal or hydraulic power stations.
• GT are step-up transformer with delta connected LV side and star connected HV side
• In Essar power salaya OLTC is used and GT consist of three single phase transformer unit.
GT SpecificationParameter Value
Rated MVA 250MVA
Rated Voltage at no load 21/420KV
Vector Group YNd1
Type Of cooling ONAN/ONAF/OFAF
NGR(Neutral Grounding Resistor)
• The suitable Neutral Grounding Resistance (NGR) should be installed between neutral point (star point) and the ground to restrict the earth fault current to 50 Amps
• it is used to limit the current flowing through ground.• it measures the resistance between the neutral and the
GND.• There two consideration to Select NGR
1) Plant capacity2) Current carrieng capacity
Bus Duct
• Different types of bus-ducts are provided as per application/ current and voltage rating.
I. IPBD (Isolated phase bus duct)II. SPBD (segregated phase bus duct)III. NSPBD (non segregated phase bus duct)
IPBD: In 20 kV,22000A Generator to Generator transformer main run
SPBD:-11kV, 1500 A between Unit transformer to Unit switchgear
NSPBD:-0.433kv, 3333.43A between service transformer to PMCC and MCC
IPBD (Isolated phase bus duct)
SPBD (segregated phase bus duct)
NSPBD (non segregated phase bus duct)
Switch Yard
• Three type of switch yard in Essar salaya power it’s divided in based on voltage levelI. HV (High Voltage Switch yard )II. MV (Medium voltage)III. LV (Low Voltage)
HV Switch yard
• Electric power is generated in Generation Station. The voltage at which is power is generated in generation station lies between 11kv to 25kv.
• SwitchYard Definition It is switching station with incoming and outgoing feeders but without the transformer. It is a type of substation but incoming feeders and outgoing feeders are of same voltage level. Some times, the out door area of a substation where the circuit breakers are located are also called switchyard of the substation A switchyard connects and disconnects lines on the grid for various reasons. The operations and equipment are essentially all at the same voltage level.
Equipment in switch yard
Main Equipment used in HV switch yard
CVT(capacitive voltage transformer) CT(current transformer) Isolator Circuit Breaker Bus bar Wave trip EMVT( electromagnetic voltage transformer) LA (lighting arrester) Earth switch
CVT(capacitive voltage transformer)
• Capacitor Voltage Transformers convert transmission
class voltages to standardized low and easily
measurable values, which are used for metering,
protection and control of the high voltage system.
CT (current transformer)
• A current transformer (CT) is used for measurement of alternating electric currents.
• A current transformer produces a reduced current accurately proportional to the current in the circuit, which can be conveniently connected to measuring and recording instruments.
Isolator
• Isolator is an off load device which is operated by remote control or local. Isolators provided in switchyard are central break type.
Types of Electrical Isolators1) Double Break Isolator2) Single Break Isolator3) Pantograph type Isolator
Circuit Breaker
• A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit
• Its basic function is to detect a fault condition and interrupt current flow
Busbar
• A busbar in electrical power distribution refers to thick strips of copper or aluminium that conduct electricity within a switchboard, distribution board, substation, or other electrical apparatus
• The size of the busbar is important in determining the maximum amount of current that can be safely carried.
Wave trap
• Wave traps are used for communication purpose during fault conditions. Wave traps offer high impedance path for high frequency signals & low impedance path for power frequency current.
EMVT (electromagnetic voltage transformer)
EMVT- Electromagnetic voltage transformer . As the name says its works in the principle of electromagnetic induction principle.Its just a stepdown transformer,stepdown voltage i.e higher voltage to meserable voltage by instruments connected to measurement and protection.
LA (lighting arrester)
• A lightning arrester is a device used on electrical power systems and telecommunication systems to protect the insulation and conductors of the system from the damaging effects of lightning
• Earth switches used in substation . in that when isolator OPEN condition earth switch is CLOSED. here any induction that passes through earth switch to ground. when isolator in CLOSED condition Earth switch should be Open
Earth Switch
CONCLUSION
The Overview of this project is about the various techniques involved in 400 KV Switchyard Of Essar Power Plant. By this we get To Know About the operation of different equipments in Switch Yard and its maintenance.
THANK YOU