JAYPEE BINA THERMAL POWER PLANT 2X250 MW

1. JAYPEE BINA THERMAL POWER PLANT
2X250 MW
Prepared By
Rahul Chauhan
Control & Instrumentation

2. OBJECTIVE OF CONTROL &
INSTRUMENTATION
 SAFE OPERATION OF PLANT.
 LONGEST EQUIPMENT LIFE.
 MINIMUM ENVIROMENTAL EFFECT.
 MAXIMUM EFFICIENCY

3. INTRODUCTION
FSSS means furnace safeguard & supervisory system ,
the system which is used in almost all types of boiler.
The system has been designed to offer maximum
protection and to ensure the execution of a safe, orderly
operating sequence in the start up and shutdown of fuel
firing equipment in a boiler and to prevent errors which
may be committed by an operator due to ignorance.

4. FSSS is designed to perform the following functions:
 Prevent any fuel firing unless a furnace purge sequence has
been completed.
 Monitor and control the proper component sequence
(Manual or Automatic) during start-up and shut-down of
fuel firing equipment.
 Make continued operation of fuel firing equipment subject
to certain safety interlocks remaining satisfied.
 Provide component status feedback to the operator and in
some cases, to the unit control system.
 Provide flame supervision when fuel firing equipment is in
service and effect a fuel trip upon certain adverse operating
conditions.
 Initiate a fuel trip when certain abnormal operating
condition exists

5.  Light Oil (LO) as the start-up fuel.
 Heavy Oil (HO) fired boiler with coal as the primary fuel / warm
up and stabilisation.
 Three elevations of high energy arc (HEA) igniters.
 Previously Three elevations of oil guns with provision for firing
LDO oil in AB elevation only, HFO in elevation AB, CD & EF
elevation.
 Now modification has been done that provision of firing LDO oil
in all 3 elevation i.e. AB , CD , EF elevation. With these
modification desk engineer will able to minimize the Boiler light
– up to synchronization time.
FSSS provided for this project is designed for
a natural circulation:

7. DESCRIPTION OF BURNER BLOCK ASSEMBLY
 Burner block assembly is divided into 14 elevation.
 There are 6 elevations of coal nozzles for firing the main fuel.
These are defined as A to F.
 There are 3 elevations of oil burner assembly for firing start up/
stabilizing fuel (EL. AB , CD & EF ).
 3 elevations acts as auxiliary air dampers ( BC, DE & FF ).
 2 nos. of over fire air compartment at the top of the wind box.
They are designated as OFA-L (Over fire air - Lower) & OFA-U (
Over fire air - Upper) respectively.
 Flame scanners are mounted at 5 different elevation i.e.
AB,BC,CD,DE & EF.
 If Secondary air is admitted to a fuel compartment in service, is
referred as Fuel air Damper.
 Secondary air is admitted to the furnace through air
compartments and fuel compartments not in service, is termed as
Auxiliary air damper.

8. FURNACE PURGE
Furnace purging is done to remove all unburnt particles
which may have been inside the furnace during earlier
unit operation.
Before Boiler is lighted up Furnace purge is done for
which following interlocks should be satisfied:
 Establish 110 V AC from UPS & 220 V DC from 4.5
mtr switchgear power to FSSS and the related
equipment.
 Establish normal drum level ( 0 mmwc NWL).
 Run at least one ID and one FD fan in service.
 Establish airflow between 30% and 40% MCR i.e. 300
to 400 TPH through the furnace.

9. If the "Purge ready” light signal does not come on after the
above conditions have been completed, check other these
condition :
 The light oil trip valve is fully closed.
 All the light oil nozzle valves are proven closed.
 The heavy oil trip valve is proven closed.
 All the heavy oil nozzle valves are fully closed.
 All PA Fans are off.
 All feeders are off.
 All hot air gates are fully closed.
 All the flame scanners sense "No Flame".
 No boiler trip command is present.
 All auxiliary dampers are modulating ( open condition ).
At the end of the five minutes, the boiler trip circuit is

10. PLACE OIL GUN IN SERVICE
Oil elevation AB is provided with Light Oil / Heavy Oil firing. Light
oil or Heavy oil firing can be selected from the console insert by
pressing the appropriate push button provided in graphic.
LIGHT OIL TRIP VALVE ( LOTV ) CONTROL
Once the Boiler trip circuit is reset and all the light oil nozzle
valves are proven closed, pressing the light oil trip valve "open"
command , will open light oil trip valve provided the light oil
header pressure is adequate.

11. LIGHT OIL TRIP VALVE (LOTV)
Open permissive:
 All LONVs are closed.
 Furnace Purge Completed & MFT reset.
 Light oil header pressure Adequate >15.6kg/cm2.
 Unit 24 V DC power available from DCDB system
Protection close:
 Light oil header press V. Low < 4.2kg/cm2.
 Atomising air pressure V. Low < 3.5kg/cm2.
 MFT acted
 The LOTV will be commanded to close on loss of +24V DC.

12. HIGH ENERGY ELECTRIC IGNITOR
The HEA igniter assembly is designed to ignite a variety of
fuel ranging from high speed diesel to heavy fuel oil. The
equipment gives high intensity electrical spark which ignite
the oil particles surrounding the spark . The major
component of BHELSPARK igniter are:
 Spark generator Box.
 Flexible cable assembly.
 Spark rod assembly.
 Spark tip.
 Retractor assembly

13. SPARK GENERATOR BOX
The spark generator box contains the high voltage step
– up transformer , produce high energy electric
discharge spark .
Input voltage = 110 VAC, 50 H
Output voltage = 3000 V DC

14. FLEXIBLE CABLE ASSEMBLEY
Flexible cable assembly is used to connect the
spark tip and the spark rod assembly to the spark
generator box. The flexibility of the cable is
required for advancing and retracting the igniter tip
using pneumatic actuator.
Length = 4000 mm
Operating voltage = 3000
V DC

15. SPARK ROD ASSEMBLY
The spark rod assembly used to connect the
spark tip to the flexible cable so the electrical
discharges are transmitted to the spark tip to
generate the sparks for ignition.
Construction : SS Wire
& SS Tube
Operating Voltage : 3000VD

16. SPARK TIP
The spark-tip is a critical component in the igniters which
converters the electrical discharge into high energy sparks.
Care should be taken to clean the tip periodically and before
any boiler light-up for reliable ignition. The tip life will reduce
and some times the tip will get damaged if it is kept for longer
duration at flame zone exposing to higher temperature.
Length of the spark tip = 180
mm
Diameter = 15.9 mm
Spark rate = 5 Sparks/second

17. RETRACTOR ASSEMBLY
The retractor assembly is a pneumatically operated system to
advance the spark tip into the burner zone and retract the
spark tip after successful ignition. The retract assembly is
equipped with solenoid valve for controlling the pneumatic
cylinder and also end point limit switches to signal the
advanced or retracted position of the spark-tip.
Air cylinder stroke = 200
mm
Air pressure = 4 – 5
kg/cm2
Solenoid operating
voltage = 110 V AC
Limit switches = 2 nos.

19. OIL ELEVATION START PERMIT
TO PLACE OIL GUN IN SERVICE “OIL ELEVATION START
PERMIT” MUST SATISFIED
 Select light oil or Heavy oil firing.
 LOTV or HOTV valve proven fully open.
 Purge Completed & MFT reset.
 Burner Tilt Horizontal & Air flow < 40% MCR. ( cold condition )
OR.
 Any oil elevation in service ( warm up condition )
OR
 Any feeder on ( Running condition ).
 Local maintenance switch in remote position.
 Oil gun engaged.
 Scavenge valve closed.
 Manual isolation valve open.

20. LDO START SEQUENCE
To place the light oil guns in service following sequence is defined in
four steps:
 HEA Rod advance command.
 Open air atom valve.
 Open LONV valve and HEA Spark command.
 Step complete.
There are two type of firing in oil elevation
(a) Pair mode (b) Elevation mode
A pair firing mode is selected when no feeder is in service .
Elevation firing mode is selected when at least one feeder is
selected.

21. TO TAKE LDO OIL GUN IN – PAIR MODE
 To place the light oil guns in service “Oil elevation start permit”
should be available.
 LDO oil can be fired at EL. AB & in pair basis. Corners 1 and 3
make one pair, while corners 2 and 4 make the other pair.
 The corners making up a pair are diagonally opposite.
 By pressing the associated pair start command ( i.e. 1-3 or 2-
4), will initiate a 70 seconds start time to place the associated
pair of LDO oil guns in service.
 When corner 1 & 3 is selected a start command is sent to oil
corner 1 , fifteen seconds later a start command is sent to oil

22.  When HEA rod is advanced and the atomising Air valve is proven
open and LONV valve gets open command & HEA igniter gets
command for sparking. 15 seconds later, HEA igniter advance and
spark command is removed.
 If the flame is established within the above 15 seconds then the oil
gun is said to have been successfully placed in service and will
continue to operate.
 If the flame is not established by the end of 15 seconds, corner trip
will be initiated which will close the oil nozzle valve & atomising valve
of the particular corner.
FLAME ON CONDITION FOR OIL = INTENSITY > 30 % & FREQ > 20 HZ
FLAME ON CONDITION FOR COAL = INTENSITY > 30 % & FREQ > 4 HZ

23. ELEVATION MODE OPERATION
Elevation mode is automatically active when the
following condition exits :
Either adjacent feeder associated with the oil elevation
is proven on .
for example Elevation AB is automatically active in
elevation mode when the adjacent feeder A OR B is
proven.
When the elevation mode is selected, the oil AB
elevation is in service as follows (assuming the “OIL
ELEVATION START PERMIT” remains established).
An elevation start command is established for corners
1 and 3 on the associated elevation.

24.  After the “elevation start” command is established, a
forty second counting period is started to establish an
“elevation start” command for corners 2 and 4.
 Corners 1 and 3 are now placed in service in the same
manner as described in the “PAIR MODE OPERATION
section.
 After the forty second counting period expires, corners 2
and 4 are placed in operation in the same manner as
described in the “PAIR MODE OPERATION”section.
 At the end of 70 secs. , a minimum of 3 LO Gun are in
service at that elevation if not, an unsuccessful
elevation start alarm is initiated. This will trip corners 1-3
and 40 seconds later corner 2-4 as described in shut
down procedure.
 Elevation mode is not in service at our station for
reliable operation .

25. OIL SHUTDOWN SEQUENCE
Heavy oil shutdown sequence in pair mode is defined in
five
steps:
 Close cmd to HONV valve.
 Open atomizing steam valve.
 Open Scavenge valve & HEA Rod advance & Spark Cmd
for 15 secs. A 5 min.Scavenge period is started.
 Close Scavenge valve & atom. steam valve.
 Step complete

26. BOILER PROTECTIONS

27. PROTECTION OF BOILER:
To detect the abnormal condition by constantly
measuring the various parameter under normal and
faulty condition . If any abnormality happened trip the
boiler to prevent from major damage.
NEEDS OF PROTECTION
 To avoid operational faults.
 Equipment safety.
 To avoid accidents .
 To avoid systems disturbances

29. BOTH ID FAN TRIP
TRIP CAUSES:
MFT
AND
Logic
Gate
PURPOSE : Protection to prevent furnace pressurization
 IDF VFD CHANNEL FAULT.
 IDF POST PURGE TRIP.
 IDF BRG TEMP V.HI.
 IDF WINDING TEMP V.HI.
 IDF VIBRATION V.HI.
 ELECTRICAL PROTECTION OPERATED.
 EPB OPERATED.
IDF – B Off (Off Feedback)
IDF – A Off (Off Feedback)

30. BOTH FD FAN TRIP
TRIP CAUSES:
MFT
AND
Logic
Gate
FDF – B Off (Off Feedback)
FDF – A Off (Off Feedback)
PURPOSE : Protection to prevent reducing firing condition.
 FDF POST PURGE TRIP.
 FDF BRG TEMP V.HI.
 FDF WINDING TEMP V.HI.
 FDF VIBERATION V.HI.
 ELECTRICAL PROTECTION OPERATED.
 EPB OPERATED.

31. DRUM LEVEL VERY
LOW
Tripping value = < - 225
mmwc
Alarm = < -125 mmwc
Time delay = 5 sec.
PURPOSE : To prevent
water wall tubes starvation.
DRUM LEVEL VERY
HIGH
Tripping value = > + 225
mmwc
Alarm = > + 125 mmwc
Time delay = 10 sec.
PURPOSE : To prevent
water carry over to super
heater header and to
turbine.
T1
T2
T3
2/3 Logic MFT
Transmitters Range = - 425 to 762 mmwc

32. FURNACE PRESSURE
VERY HIGH
Tripping value = > + 150 mmwc
Alarm 1 = > + 30 mmwc
Alarm 2 = > + 75 mmwc
PURPOSE : To stop fuel firing
under explosive tendency of
furnace , prevent furnace
structural distortion
FURNACE PRESSURE
VERY LOW
Tripping value = < - 175 mmwc
Alarm 1 = < - 30 mmwc
Alarm 2 = < - 100 mmwc
PURPOSE : To stop fuel firing
under implosive tendency of
furnace , prevent furnace
2/3
Logic
2/3
Logic
MFT
MFT
V.High 1
V.High 2
V.High 3
V.Low 1
V.Low 2
V.Low 3
2/3
Logic
2/3
Logic
MFT
MFT
V.High 1
V.High 2
V.High 3
V.Low 1
V.Low 2
V.Low 3
Switches
Switches

33. LOSS OF FUEL TRIP
The loss of fuel trip circuit becomes armed when any one
nozzle valves open from closed position in any elevation.
AND
LOGIC
GATE
LOSS OF FULE TRIP ARMING
ALL FEEDER TRIPPED
HOTV TRIPPED
OR
ALL HONV CLOSED
LOTV TRIPPED
OR
ALL LONV CLOSED

34. Once the trip circuit is armed, loss of fuel trip will occur if,
All feeders are off.
AND
HO trip valve tripped OR All HO nozzle valves closed.
AND
LO trip valve tripped OR Elev. AB All LO nozzle valves
closed.

35. UNIT FLAME FAILURE TRIP
2 S
ANY FEEDER PROVEN FLAME FAILURE TRIP
ARMING
EL . F VOTED NO FLAME
EL . E VOTED NO FLAME
EL . D VOTED NO FLAME
EL . C VOTED NO FLAME
EL . B VOTED NO FLAME
EL . A VOTED NO FLAME
AND
LOGIC
GATE

36. The Flame failure trip circuit is armed when any
one feeder is proven .
once the trip circuit is armed, flame failure trip
protection will occur if ,
Any feeder proven ( flame arming )
AND
All elevation shows voted no flame

37. EXAMPLE ELEVATION – A VOTED NO FLAME
Elevation AB 2 / 4 nozzle valves not open AND Elev. AB
scanner shows NO FLAME .
OR
Feeder A is not proven ( Off Feedback)
ELEVATION – B VOTED NO FLAME
Elev. AB 2 / 4 nozzle valves not open AND Elev. AB & BC
scanner shows NO FLAME.
OR
Feeder B OFF

38. REHEATER PROTECTION
REHEATER PROTECTION
ENABLE
(a) Boiler drum pressure > 8.2 kg/cm2
(b) Any feeder on
(c) Boiler firing
PROTECTION :
1 WHEN BOILER IS 'WORKING / REHEATER PROTECTION ENABLE
(a) GENERATOR CIRCUIT BEAKERS OPEN &. BOTH SATISAFIED
(b) HPBP OR LPBP VALVES REMAIN CLOSED
2 WHEN BOILER IS 'WORKING / REHEATER PROTECTION ENABLE
(a) TURBINE TRIPPED &
(b) HPBP OR LPBP VALVES REMAIN CLOSED
BOILER SHALL BE TRIPPED AFTER 10 Sec.
contact
Contact
Contact
2/3
Logic
MFT

39. LESS THAN FIRE BALL & 110V AC POWER
FAIL
If all feeders are off
AND
Elevation AB started and loss of 110v AC
OR
Elevation CD started and loss of 110v AC
OR
Elevation EF started and loss of 110v AC
110 V AC USED:
110v AC supply used in all OIL nozzles valve , HEA
Igniter , Feeder outlet gate , All hot air gates , mill
discharged valve.

40. LOSS OF 220 V DC
If 220v DC supply fails for 2 sec.
220v DC supply used main oil valve HOTV , HORV , LOTV &
scanner emergency damper.
LOSS OF 24V DC
 24V DC is used for functioning of DCS cards , TG governing
and field instruments ( Transmitters , switches , I/P
converter ).
PURPOSE : If 24V fails , the DCS system cannot execute
any logic

41. TOTAL AIR FLOW < 30%
If (secondary air + primary air) flow < 300 TPH.
BOILER TRIP THROUGH EMERGENCY PUSH
BUTTON
 UCP panel.
 From boiler HMI push button

42. MFT NETWORK FAILURE
If any 2 DPU cards out of 3
of MFT panels go into failed
status it will initiate MFT
Protection.
PURPOSE : This ensure that
At least 2 DPU cards are in healthy
condition at any point of time
when boiler is in service.
Failure the DPU cards leads to
unsafe condition.
2/3
Logic
DPU2
DPU3
DPU1
MFT
(DPU = DIGITAL PROCESSING
UNIT)

43. THANK YOU