CCC_Turbomachinery_Controls_System

1. CCC
CCC Turbomachinery
Turbomachinery
Controls System
Controls System

2. Who is the CCC?
Who is the CCC?
Who is the CCC?
CCC is a
CCC is a Controls Company
Controls Company dedicated to
dedicated to
making the operation of Turbomachinery
making the operation of Turbomachinery
Safe
Safe and
and Efficient
Efficient
Safe = No Missed Commissioning
No Production Loss
Efficient = Minimum Power
The CCC Product is Control Solutions
Next

3. 1974 2008
• Offices Worldwide
• +/- 400 Employees
• 8300+ Installations
• 200 Major Retrofit Projects/Year
• World’s Largest GT Retrofitter
In Operation 34 Years
In Operation 34 Years
Next

4. MTBF of Series 3 Plus controllers is 43.4 years,
or 2.5 failures per million hours of operation
Ü
Ü Multi
Multi-
-loop controllers for speed, extraction,
loop controllers for speed, extraction,
antisurge, & performance control
antisurge, & performance control
Ü
Ü Serial communications for peer to peer
Serial communications for peer to peer
and host system communications
and host system communications
Series 3+ Products
Series 3+ Products

5. Series 5 Products
Series 5 Products
Next

6. Vanguard Duplex Chassis
Vanguard Duplex Chassis
Power Supplies
IOC-555
MPU-750
Extended Card
Next

7. Series 5 Reliant Duplex
Series 5 Reliant Duplex
Switching
Module
Connector for
Remote
Switch Module
Status
Indicators
Manual
Switchover
Pushbuttons
Same
Electronics
Assembly and
Terminations
as Reliant SN
Next

8. Guardian
Guardian®
®
Overspeed Trip System
Overspeed Trip System
• API-670
Compliant
• 2oo3 Voting
of Speed
Modules
• Redundant
Power
Supplies
• Hot-Swap
Speed
Modules
• Modbus
Comms
Next

9. Vantage
Vantage®
®
Steam Turbine Governors
Steam Turbine Governors
• Vantage GP
for API-611
General
Purpose
Turbines
• Vantage GD
for Generator
Drive
Turbines
• Local HMI for
Configuration
and
Maintenance
• Reliant in
an IP-54
Enclosure
Next

10. • NEMA 4 enclosure
• Touch Screen Color
Graphics Operator I nterface
– Param eter m onitoring
– Alarm s ( visual and audible)
– Events and data logging
– Real-tim e trending of process
data
– Control loop tuning and
m aintenance screens
– Rem ote netw ork and w eb data
access
• Optional I nstrum entation
and Value Packages
Air Miser
Air Miser®
®TL Enclosure
TL Enclosure
Next

11. Ü
Ü Class 1, Div 2 / Class 1 Zone 2
Class 1, Div 2 / Class 1 Zone 2
Ü
Ü ATEX Group 2 Class 3
ATEX Group 2 Class 3
Ü
Ü Simplex or
Simplex or “
“hot backup
hot backup”
” redundant
redundant
Ü
Ü All AO
All AO’
’s have built
s have built-
-in feedback loops to identify
in feedback loops to identify
hardware or wiring problems
hardware or wiring problems
Series 3++ Controllers
Series 3++ Controllers
Ü
Ü On
On-
-board temperature
board temperature
monitoring
monitoring
Ü
Ü On
On-
-board power supply
board power supply
voltage monitoring
voltage monitoring
Ü
Ü Wired Ethernet version
Wired Ethernet version
Ü
Ü Completely backward
Completely backward
compatible with S3+
compatible with S3+

12. Raising the Bar Advanced
Raising the Bar Advanced
Constraint Control
Constraint Control
Ü
Ü Upstream
Upstream
improved control strategies for load sharing, expanders,
improved control strategies for load sharing, expanders,
integration of networks across platforms
integration of networks across platforms
Ü
Ü Midstream
Midstream
improved control strategies for Boil Off Gas networks,
improved control strategies for Boil Off Gas networks,
intense focus on all primary LNG services
intense focus on all primary LNG services
Ü
Ü Downstream
Downstream
broader approach to process control, rather than just
broader approach to process control, rather than just
Turbomachinery control. Advanced control strategies for
Turbomachinery control. Advanced control strategies for
Ethylene, FCCU and PTA Plants. (Next focus is Ammonia).
Ethylene, FCCU and PTA Plants. (Next focus is Ammonia).
Next

13. CCC Installations
CCC Installations -
- Indonesia
Indonesia
Ü
Ü PT. Pupuk
PT. Pupuk Iskandar
Iskandar Muda
Muda
Ü
Ü PT. Pupuk
PT. Pupuk Sriwidjaya
Sriwidjaya
Ü
Ü PT. Pupuk
PT. Pupuk Kujang
Kujang
Ü
Ü PT. Pupuk Kalimantan
PT. Pupuk Kalimantan Timur
Timur
Ü
Ü PT. DSM
PT. DSM Kaltim
Kaltim Melamine Indonesia
Melamine Indonesia
Ü
Ü PT. Amoco Mitsui PTA
PT. Amoco Mitsui PTA
Ü
Ü PT.
PT. Polysindo
Polysindo Eka
Eka Perkasa
Perkasa
Ü
Ü PT. Chandra
PT. Chandra Asri
Asri
Ü
Ü Pertamina
Pertamina / Refinery (WGC
/ Refinery (WGC Exor
Exor Project)
Project)
Ü
Ü ConocoPhillips
ConocoPhillips Indonesia
Indonesia
Ü
Ü ExxonMobil
ExxonMobil Oil Indonesia
Oil Indonesia
Ü
Ü Total
Total Indonesie
Indonesie
Ü
Ü PT.
PT. Kangean
Kangean Energi
Energi Indonesia
Indonesia
Ü
Ü BP
BP Tangguh
Tangguh LNG
LNG
Ü
Ü PT.
PT. Badak
Badak LNG
LNG
Ü
Ü PT.
PT. Arun
Arun LNG
LNG
Ü
Ü PT. Indonesia Power (PLN)
PT. Indonesia Power (PLN)
Ü
Ü Etc.
Etc.
Next

14. 1
PT
Section 1
out
out
RSP
A
LSIC
Section 2
1A
UIC
1A
UIC
Serial
network
Train A
Next
Typical Single Train Controls
Typical Single Train Controls
(Suction Pressure Controls)
(Suction Pressure Controls)
Antisurge Controls System
Performance Controls
System

15. Compressor Refresher
Compressor Refresher
Next

16. Compressor Type
Compressor Type
Next
Compressors
Positive Displacement
Compressor
Dynamic Compressor
Reciprocating Compressor
Rotary Compressor
Membrane Compressor
Screw Compressor
Centrifugal
Axial
CCC Focus
CCC Focus

17. Where do the different types of
Where do the different types of
compressor fit?
compressor fit?
Next

18. Types of Compressor
Types of Compressor -
- Dynamic
Dynamic
Compressors
Compressors
Axial Compressor Centrifugal Compressor
Next

19. Types of Compressor
Types of Compressor -
- Dynamic
Dynamic
Axial Compressors
Axial Compressors
Stator Blades
Rotor
Blades
Casing
Rotor Blades
Stator
Blades
Casing
Shaft
Next
Rotor
Stator

20. Cross section of axial compressor
Cross section of axial compressor
Compressor outlet nozzle
Rotor blades
Labyrinth seals
Guide-vane actuator linkage
Stator Blades
Compressor inlet nozzle
Thrust bearing
Adjustable guide vanes
Next

21. Barrel (Centrifugal)
Barrel (Centrifugal) Bullgear (Centrifugal)
Bullgear (Centrifugal)
Types of Compressor
Types of Compressor –
– Dynamic
Dynamic
Centrifugal Compressors
Centrifugal Compressors
Next

22. Compressor inlet nozzle
Thrust bearing
Journal bearing
Shaft and labyrinth seal
Impeller inlet labyrinth seals
Discharge volutes
Impellers
Drive coupling
Casing
(horizontally split flange)
Compressor discharge nozzle
Horizontally Split Type (Centrifugal)
Horizontally Split Type (Centrifugal)
Horizontally Split Type (Centrifugal)
Next

23. Types of Compressor
Types of Compressor -
- Picture of
Picture of
Horizontally Split Type (Centrifugal)
Horizontally Split Type (Centrifugal)
Next

24. Types of Compressor
Types of Compressor -
- Principal of
Principal of
Operation (Centrifugal)
Operation (Centrifugal)
Next

25. Single-Section, Three-Stage Single-Case, Two-Section, Six-Stage
Types of Compressor
Types of Compressor -
- Classifications
Classifications
W hat is the function of this cooler?
I ntercooling
I ntercooling reduces energy consum ption
reduces energy consum ption
but results in having m ultiple com pressor m aps
but results in having m ultiple com pressor m aps
w hich need separate
w hich need separate antisurge
antisurge protection
protection
Next

26. Parallel Network
Two-Case, Two-Section, Six-Stage
Series Network
Types of Compressor
Types of Compressor -
- Classifications
Classifications
Next

27. Why Compressor Surge
Why Compressor Surge
…
…and what happens
and what happens
when they do
when they do
Next
Surge Phenomenon
Surge Phenomenon

28. • From A to B…….20 - 50 ms…………….. Drop into surge
• From C to D…….20 - 120 ms…………… Jump out of surge
• A-B-C-D-A……….0.3 - 3 seconds……… Surge cycle
Qs, vol
Pd
Machine shutdown
no flow, no pressure
• Electro motor is started
• Machine accelerates
to nominal speed
• Compressor reaches
performance curve
Note: Flow goes up faster
because pressure is the
integral of flow
• Pressure builds
• Resistance goes up
• Compressor “rides” the curve
• Pd = Pv + Rlosses
Pd = Compressor discharge pressure
Pv = Vessel pressure
Rlosses = Resistance losses over pipe
Developing the surge cycle on the
Developing the surge cycle on the
compressor curve
compressor curve
Pd
Pv
Rlosses
B A
C
D
Next

29. Ü
Ü Rapid flow oscillations
Rapid flow oscillations
Ü
Ü Thrust reversals
Thrust reversals
Ü
Ü Potential damage
Potential damage
FLOW
PRESSURE
TEMPERATURE
TIME (sec.)
1 2 3
TIME (sec.)
1 2 3
TIME (sec.)
1 2 3
Major Process Parameters during
Major Process Parameters during
Surge
Surge
• Rapid pressure
oscillations with
process instability
• Rising temperatures
inside compressor
Next

30. Some surge consequences
Some surge consequences
Ü
Ü Unstable flow and pressure
Unstable flow and pressure
Ü
Ü Damage in sequence with increasing
Damage in sequence with increasing
severity to seals, bearings, impellers,
severity to seals, bearings, impellers,
shaft
shaft
Ü
Ü Increased seal clearances and leakage
Increased seal clearances and leakage
Ü
Ü Lower energy efficiency
Lower energy efficiency
Ü
Ü Reduced compressor life
Reduced compressor life
Next

31. Factors leading to onset of
Factors leading to onset of
surge
surge
Ü
Ü Startup
Startup
Ü
Ü Shutdown
Shutdown
Ü
Ü Operation at reduced throughput
Operation at reduced throughput
Ü
Ü Operation at heavy throughput with:
Operation at heavy throughput with:
-
- Trips
Trips
-
- Power loss
Power loss
-
- Operator errors
Operator errors
-
- Process upsets
Process upsets
-
- Load changes
Load changes
-
- Gas composition changes
Gas composition changes
-
- Cooler problems
Cooler problems
-
- Filter or strainer problems
Filter or strainer problems
-
- Driver problems
Driver problems

32. Standard Antisurge
Standard Antisurge
Control Vs CCC Controls
Control Vs CCC Controls
System
System
Next

33. Flow
Pressure
minimum speed
maximum speed
surge limit
stonewall or
choke limit
power limit
process limit
stable zone
stable zone
of operation
of operation
adding control
margins
Actual available
operating zone
CCC Business in Constraint Control
CCC Business in Constraint Control
Next

34. Flow
Pressure
minimum speed
maximum speed
surge limit
stonewall or
choke limit
power limit
process limit
stable zone
stable zone
of operation
of operation
adding control
margins
Actual available
operating zone
CCC Business in Constraint Control
CCC Business in Constraint Control
Next

35. Expanding the Operating Envelope
Expanding the Operating Envelope
Operating Point
Limit
Operating Point
Setpoint
Base Ingredients:
- Advanced algorithms
- Rate of change feed forward signals
- Fast hardware
Limit
Setpoint
General
Purpose
Control
CCC
Control
Next

36. Standard Antisurge Control
Standard Antisurge Control
1
UIC
Compressor
Compressor
1
FT
1
PsT
Process
Suction
1
PdT
Next
Antisurge
Controller
Recycle Valve

37. Conventional Control Using Separate
Conventional Control Using Separate
Performance Recycle
Performance Recycle
Compressor
Compressor
Process
Suction 1
UI
C
1
F
T 1
PsT
1
PdT
1
PIC
Next
Conventional
Capacity/ Perform ance
Controller
Additional Recycle Valve

38. Why Invest in Advanced
Why Invest in Advanced
Controls?
Controls?
Next

39. How Will CCC
How Will CCC Control
Control?
?
Ü
ÜAntisurge Control?
Antisurge Control?
Ü
ÜCapacity Control?
Capacity Control?
Next

40. CCC Controls System
CCC Controls System
Next
1
UIC
VSDS
Compressor
1
FT
1
PsT
1
TsT
Process
Suction
1
PdT
1
TdT
1
ST
1
PIC
1
HIC
Load
Serial
network
Antisurge
Controller
Perform ance
Controller

41. Control System Objective
Control System Objective
Control System Objectives:
Control System Objectives:
Ü
Ü The control system objective is to keep the
The control system objective is to keep the
process on its Primary Process Variable (PV)
process on its Primary Process Variable (PV)
set
set-
-point, and to return it to set
point, and to return it to set-
-point as quickly
point as quickly
as possible after a process disturbance
as possible after a process disturbance
Ü
Ü The control system has to keep the process
The control system has to keep the process
on/return to set
on/return to set-
-point while operating within
point while operating within
compressor operating envelope limits, including
compressor operating envelope limits, including
protection against surge and surge damage
protection against surge and surge damage
Next

42. Challenges of Compressor
Challenges of Compressor
Control System
Control System
The ingredients of a successful compressor control system
The ingredients of a successful compressor control system
are:
are:
An algorithm that can accurately locate the operating point
An algorithm that can accurately locate the operating point
and its corresponding surge limit
and its corresponding surge limit
A controller execution speed that will allow a digital controlle
A controller execution speed that will allow a digital controller
r
to emulate immediate analog control
to emulate immediate analog control
Control responses that allow different margins of safety for
Control responses that allow different margins of safety for
different operating conditions
different operating conditions
Advanced control strategies that can avoid the negative
Advanced control strategies that can avoid the negative
effects of loop interaction
effects of loop interaction
A quick acting, correctly sized antisurge control valve
A quick acting, correctly sized antisurge control valve
The elimination of unnecessary dead time or lag time within
The elimination of unnecessary dead time or lag time within
the system
the system
Valid load sharing strategies
Valid load sharing strategies
Next

43. Standard Control VS CCC
Standard Control VS CCC
Controls
Controls
Ü
Ü Standard
Standard Ü
Ü CCC
CCC
Next
1
U
I
C
VSDS
Compressor
1
F
T 1
P
s
T
1
T
s
T
Process
Suction
1
P
d
T
1
T
d
T
1
S
T 1
P
I
C
1
H
I
C
Load
Serial
network
Compressor
Compressor
Process
Suction 1
U
I
C
1
F
T
1
P
s
T
1
P
d
T
1
P
I
C

44. Standard Control VS CCC
Standard Control VS CCC
Controls
Controls
Ü
Ü Standard
Standard
15% surge margin
15% surge margin
Quick opening valves
Quick opening valves
No control of process
No control of process
variable via recycle
variable via recycle
No invariant coordinates
No invariant coordinates
Concentrating on
Concentrating on
‘
‘Protection
Protection’
’
Ü
Ü CCC
CCC
Typically 8% surge margin
Typically 8% surge margin
Linear valves with
Linear valves with
positioners for control
positioners for control
across 100% range
across 100% range
Control of primary process
Control of primary process
variable by recycle when
variable by recycle when
speed limit is reached
speed limit is reached
Can handle varying
Can handle varying
molecular weight gases
molecular weight gases
Concentrating on
Concentrating on ‘
‘Control
Control
and Protection
and Protection’
’
Next

45. CCC
CCC Control
Controller protection
ler protection
How CCC
How CCC Antisurge
Antisurge Controller
Controller
protects compressor against
protects compressor against
surge?
surge?
Next

46. 1
UIC
VSDS
Compressor
1
FT
1
PsT
1
PdT
• The antisurge controller UIC-1 protects the compressor
against surge by opening the recycle valve
Discharge
Suction
Rc
qr
2
Rprocess
Rprocess+valve
Antisurge Controller Operation Protection #1
Antisurge Controller Operation Protection #1
The Surge Control Line (SCL)
The Surge Control Line (SCL)
Next

47. A
Rc
B
Ü
Ü When the operating point
When the operating point
crosses the SCL, PI
crosses the SCL, PI
control will open the
control will open the
recycle valve
recycle valve
Ü
Ü PI control will give
PI control will give
adequate protection for
adequate protection for
small disturbances
small disturbances
SLL = Surge Limit Line
SCL = Surge Control Line
qr
2
Antisurge Controller Operation Protection #1
Antisurge Controller Operation Protection #1
The Surge Control Line (SCL)
The Surge Control Line (SCL)
• PI control will give stable control during steady state
recycle operation
• Slow disturbance example
Next

48. A
Rc
B
• When the operating point
moves quickly towards the
SCL, the rate of change
(dS/dT) can be used to
dynamically increase the surge
control margin.
• This allows the PID controller
to react earlier.
• Smaller steady state surge
control margins can be used
w/o sacrificing reliability.
• Fast disturbance example
Q
2
Antisurge Controller Operation Protection #2
Antisurge Controller Operation Protection #2
Moving The Surge Control Line (SCL)
Moving The Surge Control Line (SCL)
SLL = Surge Limit Line
SCL = Surge Control Line
Next

49. Antisurge Controller Operation Protection #3
Antisurge Controller Operation Protection #3
The Recycle Trip
The Recycle Trip®
®
Line
Line (
(RTL
RTL)
)
Benefits:
– Reliably breaks the
surge cycle
– Energy savings due to
smaller surge margins
needed
– Compressor has more
turndown before
recycle or blow-off
– Surge can be
prevented for virtually
any disturbance
SLL = Surge Limit Line
RTL = Recycle Trip Line
SCL = Surge Control Line
Output
to Valve
Time
Open-loop Response
PI Control Response
PI Control Step Change
+
To antisurge valve
Total Response
Rc
Q
2
OP
Next

50. After time delay C
After time delay C2
2 controller checks if Operating Point is back to
controller checks if Operating Point is back to
safe side of
safe side of Recycle Trip
Recycle Trip®
®
Line
Line
-
- If
If Yes
Yes: Exponential decay of
: Exponential decay of Recycle Trip
Recycle Trip®
®
response
response.
.
Output
to valve
Time
One step response
PI Control
Recycle Trip®
Total
100%
0%
C2
Multiple step response
Output
to valve
Time
PI Control
Recycle Trip®
Total
C2 C2 C2
What if one Recycle Trip
What if one Recycle Trip®
®
step
step
response is not enough?
response is not enough?
- If No: Another step is added to the Recycle Trip®
response.
Next

51. Output to
Recycle Valve
Input
Output to
Turbine Valve
Speed Inputs
Speed Inputs
Antisurge Inputs
Antisurge Inputs
Process Variable Inputs
Process Variable Inputs
Serial
Communication
Link CCC-DCS
Flow
Pressure
Temperature
Gas Data
(Field
Transmitter)
Next
Integrated control Decoupling of
Integrated control Decoupling of
Performance and
Performance and Antisurge
Antisurge control
control

52. ∆Po
PIC-SP
Rc
Ps
S
L
L
S
C
L
A
C
B
Integrated control Decoupling of
Integrated control Decoupling of
Performance and
Performance and Antisurge
Antisurge control
control
2.
2. The decoupling control starts to act
The decoupling control starts to act
Performance control send request
Performance control send request
to increase speed
to increase speed
3.
3. The speed increasing combined with
The speed increasing combined with
antisurge
antisurge valve opening, then,
valve opening, then,
The trace of operating line as shown
The trace of operating line as shown
4.
4. The net control effect is more
The net control effect is more
stable operation even with large
stable operation even with large
process disturbance
process disturbance
5.
5. This decoupling control is can
This decoupling control is can
reduce the control safety margin,
reduce the control safety margin,
Therefore it can achieve energy
Therefore it can achieve energy
saving and safe operation
saving and safe operation
1. When operating at Point A, process
1. When operating at Point A, process
encounters a large disturbance,
encounters a large disturbance,
operating point will move to Point B
operating point will move to Point B
Next

53. Antisurge Controller Operation
Antisurge Controller Operation
Protection #4
Protection #4 “
“Safety On
Safety On”
”
How about if the protection not capable
How about if the protection not capable
against surge?
against surge?
Compressor has real surge
Compressor has real surge
What will CCC controller do?
What will CCC controller do?
Next

54. SCL = Surge Control Line
• If Operating Point crosses the Safety
On® Line the compressor is in surge
SLL = Surge Limit Line
RTL Line = Recycle Trip®
• The Safety On® response shifts the
SCL and the RTL to the right
New SCL
New RTL
• Additional safety or surge margin is
added
Additional surge margin
• PI control and Recycle Trip® will
stabilize the machine on the new SCL
SOL = Safety On®
Line
Pressure
axis
Flow axis
Antisurge Controller Operation Protection #5
Antisurge Controller Operation Protection #5
“
“Safety On
Safety On”
”
Next

55. CCC
CCC
LOAD SHARING CONTROLS
LOAD SHARING CONTROLS
SYSTEM
SYSTEM
Next

56. Ü
Ü Compressors are often operated in parallel and sometimes in seri
Compressors are often operated in parallel and sometimes in series
es
Ü
Ü The purposes of networks include:
The purposes of networks include:
Redundancy
Redundancy
Flexibility
Flexibility
Incremental capacity additions
Incremental capacity additions
Ü
Ü Often each compressor is controlled, but the network is ignored
Often each compressor is controlled, but the network is ignored
Ü
Ü Compressor manufacturers often focus on individual machines
Compressor manufacturers often focus on individual machines
Ü
Ü A
A “
“network view
network view”
” of the application is essential to achieve good
of the application is essential to achieve good
surge protection and good performance control of the network.
surge protection and good performance control of the network.
Compressor networks
Compressor networks
Next

57. Control system objectives for compressors in parallel:
Control system objectives for compressors in parallel:
Maintain the primary performance variable (in this case
Maintain the primary performance variable (in this case
suction pressure), and then:
suction pressure), and then:
Optimally divide the load between the compressors in the
Optimally divide the load between the compressors in the
network, while:
network, while:
•
• Minimizing risk of surge
Minimizing risk of surge
•
• Minimizing energy consumption
Minimizing energy consumption
•
• Minimizing disturbance of starting and stopping
Minimizing disturbance of starting and stopping
individual compressors
individual compressors
•
• Operating within limits
Operating within limits
Load Sharing
Load Sharing
Next

58. Load Sharing Control system types:
Load Sharing Control system types:
1. Base and Swing Load Sharing system
1. Base and Swing Load Sharing system
2. Equal Flow Load Sharing system
2. Equal Flow Load Sharing system
3. CCC Equidistance Load Sharing controls system
3. CCC Equidistance Load Sharing controls system
Load Sharing
Load Sharing
Next

59. Process
PIC
1
1
UIC
VSDS
Compressor 1
2
UIC
VSDS
Compressor 2
HIC
1
Suction
header
Swing
machine
Base
machine
Notes
• All controllers act
independently
• Transmitters are
not shown
Base and Swing Load Sharing
Base and Swing Load Sharing
Flow Diagram for Control Process
Flow Diagram for Control Process
Next

60. Rc,1
qr,1
2
Rc,2
qr,2
2
Compressor 1 Compressor 2
PIC-SP
Swing machine Base machine
QC,2= QP,2
QC,1
QP,1
where:
QP = Flow to process
QC= Total compressor flow
QC - QP = Recycle flow
QP,1
QP,1 + QP,2 = QP,1 + QP,2
Notes:
• Base loading is inefficient
• Base loading increases the risk of surge
since compressor #1 will take the worst
of any disturbance
• Base loading requires frequent operator
intervention
• Base loading is NOT recommended
Base and Swing Load Sharing
Base and Swing Load Sharing
Parallel Compressor Control
Parallel Compressor Control
QP,2
Next

61. Process
PIC
1
1
UIC
Compressor 1
VSDS
Compressor 2
Suction
header
Notes
• Performance controllers
act independent of
antisurge control
• Higher capital cost due to
extra Flow Measurement
Devices (FMD)
• Higher energy costs due
to permanent pressure
loss across FMD’s
1
FIC
2
FIC
2
UIC
out
out
out
RSP
RSP
RSP
RSP
RSP
RSP
out
out
RSP
RSP
Equal Flow Load sharing
Equal Flow Load sharing
Flow Diagram for Control Process
Flow Diagram for Control Process
VSDS
Next

62. Notes:
• Requires additional capital investment in
FMD’s
• Requires additional energy due to
permanent pressure loss across FMD’s
• Poor pressure control due to positive
feedback in control system (see next)
• Equal flow division is NOT recommended
Rc,1
qr,1
2
Rc,2
qr,2
2
PIC-SP
QP,1 QP,2
QC,2
Equal flow Equal flow
QP,1 = QP,2
Equal Flow Load sharing
Equal Flow Load sharing
Parallel Compressor Control
Parallel Compressor Control
Compressor 1 Compressor 2
where:
QP = Flow to process
QC= Total compressor flow
QC - QP = Recycle flow
Next

63. Notes
• All controllers are
coordinating
control responses
via a serial network
• Minimizes recycle
under all operating
conditions
Process
1
UIC
VSDS
Compressor 1
VSDS
Compressor 2
Suction
header
1
LSIC
2
UIC
out
RSP
Serial
network
out
RSP
2
LSIC
1
MPIC
Serial
network
Serial
network
CCC Equidistance Load sharing
CCC Equidistance Load sharing
Flow Diagram for Control Process
Flow Diagram for Control Process
Next

64. PIC-SP
0.1
0.2
0.3
DEV = 0
0.1
0.2
0.3
DEV1 DEV2
SCL = Surge Control Line
Rc,1
qr,1
2
Rc,2
qr,2
2
Compressor 1 Compressor 2
Dev1 = Dev2
Q1 = Q2
N1 = N2
Notes:
• Maximum turndown (energy savings) without recycle or blow-off
• Minimizes the risk of surge since all machines absorb part of the
disturbance
• Automatically adapts to different size machines
• CCC patented algorithm
CCC Equidistance Load sharing
CCC Equidistance Load sharing
Parallel Compressor Control
Parallel Compressor Control
Next

65. Loop
Decoupling
FA
Mode
PI
Loop
Decoupling
+
Analog Inputs
+
DEV
To antisurge valve To performance
control element
PID
Load
balancing
PV
PV
SP
Primary
response
DEV DEV
DEV
DEV from other
loadsharing
controllers
Primary
response
Average
SP
The load balancing response
The load balancing response
Loadsharing
Loadsharing
Controller
Controller
Antisurge
Antisurge
Controller
Controller
Master
Controller
RT
Next

66. CCC LOAD SHARING
CCC LOAD SHARING
Control System Drawing
Control System Drawing
Next
MASTER CONTROLLER
(Suction Header Controls)
LOAD SHARING CONTROLLER
ANTISURGE CONTROLLER

67. End Slides
End Slides
Thank You very much for your
Thank You very much for your
kind attention and cooperation
kind attention and cooperation
PT Putranata Adi Mandiri
Jl Kartini VIII No. 9
Jakarta 10750
Tel: (021) 6007850
Fax: (021) 6007846
Email: pamccc@cbn.net.id