PRESENTATION ONIN-PLANT TRAINING
DURATION:01-07-2015 to 28-07-2015
AT
Kanti Bijlee Utpadan Nigam Limited
(A Subsidiary of NTPC)
Kanti, Muzaffarpur, Bihar
2. Formerly
• Vaishali Power Generating Company Limited.(VPGCL)
• Owned by “Bihar State Electricity Board”
Currently
• Kanti Bijlee Utpadan Nigam Limited. (KBUN)
• A joint venture of NTPC (64.57%) and BSEB (35.43%)
Features
• It is totally coal fired thermal power station.
Capacity
• There are two units in stage-I each of 110MW under operation.
• Stage-II having capacity of 2x195MW is at stage of completion.
4. The coal is unloaded either manually or with the help of
wagon tippler into the hopper to the conveyer belt.
Coal is passed through metal detectors in order to remove
metals present in coal.
Stones from coal is removed manually in its journey
through conveyer belt.
Then the coal is passed through vibrating screen where
coal of 5mm is separated from large coals.
Then coal is crushed in crusher and passed through metal
detectors to remove iron particles.
Coal is then supplied from coal bunker to pulverizing mill.
Coal dust comes out of this mill.(KBUNL have ball mills)
5.
6. At KBUNL water tube boiler is employed for steam generation.
Fuel is burnt in furnace . The pulverized coal is dried by P.A fans and
secondary air is provided by F.D fan for pulverized coal combustion in
the furnace.
Water from boiler is passed through the down comers to the bottom
ring header. From bottom ring header water goes to water walls for
heat absorption and conversion in to steam.
Bottom of furnace is open to allow ash/clinkers to fall freely in to the
bottom ash hopper. And flue gas is used in economizer and reheaters.
Then it is discharged with the help of I.D fan in to atmosphere.
7.
8.
9. High pressure
turbine
• It is of single
flow design with
eight stages of
blading.
• Each stage has
moving and
stationary
blades.
• Superheated
steam(at 1100⁰c)
from boiler drum
enters in to it.
Intermediate
pressure turbine
• Double flow design
with seven stages
of blading .
• Each stage has
moving and
stationary blades.
• Reheated steam(at
535⁰ c) from H.P
turbine outlet
enters in to it.
Low pressure turbine
• It is also of double flow
design with 6 stages in
front and rear flow
paths.
• Each stage has moving
and stationary blades.
• Stem out of I.P. turbine
directly enters in to it.
10. Rating Continuous
Active Output 110 MW
Rated Voltage 11000 +/- 5%V
Rated Current 7220 A
Power Factor 0.8 Lagging
Frequency 50 Hz
Excitation System Static type
Field Current at
Rated Output
1335 A
Type of Cooling
System
Hydrogen Cooled
Hydrogen Pressure 2 Ata
No. of H₂ Cooled
Elements
06
Cooling Medium for
H₂
Soft water
11. Mechanical power produced at the shaft of
the turbine is used to rotate rotor.
Rotating Magnetic flux produced by rotor
cuts stator conductor flux and from
electromagnetic induction, electricity is
produced .
Rotor runs at 3000 rpm, produces 3-phase
voltage at 11kv , and of 50 HZ frequency.
Oil shielded hydrogen is used for the cooling
purpose of generator.
12. KBUNL has a capacity to generate 220 MW of
electricity but only one unit is working and
another is under R&M process. 90 MW is
generated out of 110 MW.
The transmission is done through 3-
phase , double circuit system.
With the help of station transformer 11kv
is step up to 220 kv and fed to substation.
13. Relay circuit
• A protective device that operate during faulty condition and
gives command to circuit breaker to trip. Mainly the
electromagnetic induction relays are used.
Fault Locator
By comparing voltage and current the relay measures the line
impedance up to the point of fault and locate the position of
fault from the previous knowledge of line impedance.
Switchgear
• Switches used in substation for making or breaking the
electrical contacts in convenient way. There are two type of
switches air switch and oil switch.
It is the brain of any substation. All necessary steps about
Transmission , protection, Charging etc. are carried out in the
control room.
Measuring instruments of the control room:-
14. Voltmeter and Ammeter
• As the names imply they are used for measuring voltage
and current respectively.
Power meter
• Used to measure the power in standard unit of MW or KW.
Circuit screen
• A computer arrangement in which current information
about transmission line is seen.
Battery room
Consists of several batteries and chargers for
emergency purpose.
15. It consists of following equipments :-
Transformer
• The autotransformer used in power station. It has three
windings primary, secondary and tertiary. The 220kv voltage
is fed as input to primary by step down 132kv fed to KBUNL as
input.
Circuit Breaker (SF6 at KBUNL)
• Used for closing or opening an electrical circuit under normal or
abnormal conditions. These circuit breakers are equipped with
trip coil connected to relay, design to open breaker
automatically
Tower
• We have suspension type tower called as ‘A’ type tower. The
peak point angle is 0⁰ to 2⁰. In this type conductor is
suspended with an insulator. Guard ring Is used to balance
the capacitive current in transmission lines.
16. Current transformer
• Used to measure the current level such that it can be control
easily.
Bus isolators
• Used to isolate bus bars.
Lightning arrestor
• Used to protect the transmission line and connected
equipment during lightening .
Wave Trap
Wave trap which changes the frequency 50Hz to 500Hz can be
used for communicate between power plants.
18. Why cylindrical pipes are used in switchyard instead
of wire conductor ?
Because of following purpose :-
•Safety.
•Reduce Ferranti Effect.
•Reduce the effect of vibration during opening and closing of
circuit breakers and isolators.
19. Why motor is used to rotate the shaft of turbine, when
the turbine is not in operation?
20. Why motor is used to rotate the shaft of turbine, when
the turbine is not in operation?
This is because in case of any fault if
production of plants stops then bearing
motor rotates rotor shaft of turbine
continuously at 65 rpm. This is because if
shaft doesn’t rotate then due to load it may
bend.