Dr. A. Afzalian
Dept. of Computer & Control Systems Engineering,
The Power & Water University of Technology (PWUT)
A Short Course, April 2005
Process
Automation
Outline:
•
Examples of automated processes
•
Types of plants and controls
•
Automation hierarchy
•
Control System Architecture
Process Automation
2/27
Automation Applications
 Power generation
hydro, coal, gas, oil, shale, nuclear, wind, solar
 Transmission
electricity, gas, oil
 Distribution
electricity, water
 Process
paper, food, pharmaceutical, metal, processing,
glass, cement, chemical, refinery, oil & gas
 Manufacturing
computer aided manufacturing (CIM), flexible
fabrication, appliances, automotive, aircrafts
 Storage
silos, elevator, harbor, deposits, luggage handling
 Building
heat, ventilation, air conditioning (HVAC), access
control, fire, energy supply, tunnels, highways,....
 Transportation
rolling stock, street cars, sub-urban trains,
busses, cars, ships, airplanes, satellites,...
Process Automation
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Examples of Automated Plants
Cars
Appliances control (windows, seats, radio,..)
Motor control (exhaust regulations)
ABS and EPS, brake-by-wire, steer-by-wire
19% of the price is electronics, (+10% per year)
Airplanes Avionics
flight control, autopilot
flight management
flight recording, black boxes
diagnostics
“fly-by-wire”
Process Automation
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Examples of Automated Plants
Flexible Automation, Manufacturing
Numerous conveyors,
robots, CNC machines,
paint shops, logistics.
Process Automation
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Examples of Automated Plants:
Oil, Gas and Petrochemicals
Distribution:
(environmental protection)
Upstream:
from the earth to the refinery
(High pressure, saltwater, inaccessibility
explosive environment with gas)
Downstream:
(extreme explosive environment)
Process Automation
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Examples of Automated Plants:
Power plants
• Raw materials
supply
• Primary process
(steam, wind)
• Personal, plant and
neighbourhood
safety
• Environmental
impact
• Generation
process
(voltage/frequency)
• Energy distribution
(substation)
Process Automation
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Examples of Automated Plants:
Waste treatment, incinerators
• Raw material supply
• Burning process
• Smoke cleaning
• Environmental control
• Co-generation process (steam, heat)
• Ash analysis
• Ash disposal
Process Automation
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Examples of Automated Plants:
Water treatment
Managing pumps, tanks, chemical composition, filters, movers,..
Process Automation
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Automation Systems Manufacturers
Company
Location
Major mergers
ABB
CH-SE
Brown Boveri, ASEA, CE, Alfa-Laval, Elsag-Bailey
Siemens
DE
Plessey, Landis & Gyr, Stäfa, Cerberus,..
Ansaldo
IT
Emerson
US
General Electric
US
Honeywell
US
Rockwell Automation
US
Allen Bradley, Rockwell,..
Alstom
FR
Alsthom, GEC, CEGELEC, ABB Power,..
Schneider Electric
FR
Télémécanique, Square-D, ...
Invensys
UK
Foxboro, Siebe, BTR, Triconex,…
Hitachi
JP
Yokogawa
JP
Fisher Rosemount
€ 80 B / year business, growing 5 % annually
Process Automation
10/27
Technical Necessity of Automation
Processing of the information flow
 Enforcement of safety and availability
 Reduction of personal costs
Process Automation
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Expectations of Automation
 Process Optimisation
– Energy, material and time savings
– Quality improvement, reduction of waste, pollution control
– compliance with laws, product tracking
– Increase availability, safety
– Fast response to market
– Connection to management and accounting
 Acquisition of large number of “Process Variables”, data mining
 Personal costs reduction
– Simplify interface
– Assist decision
– Require data processing, displays, data base, expert systems
 Human-Machine Interface (MMC = Man-Machine Communication)
 Asset Optimisation
– Automation of engineering, commissioning and maintenance
– Software configuration, back-up and versioning
– Maintenance support
 Engineering Tools
Process Automation
12/27
Data Quantity in Different Plants
• Power Plant (25 years ago)
– 100 measurement and action variables (called "points")
– Analog controllers, analog instruments
– one central "process controller" for data monitoring and protocol.
•
Thermal power plant (today)
– 10000 points, comprising:
» 8000 binary and analog measurement points and
» 2000 actuation point
– 1000 micro-controllers and logic controllers
• Nuclear Power Plant
– three times more points than in conventional power plants
• Electricity distribution network
– 100’000 – 10’000’000 points
•
Data reduction and processing is necessary to operate plants
Process Automation
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Automation Hierarchy
• Little difference in the overall
architecture of different
applications control systems.
• ANS/ISA standard
Enterprise
Manufacturing
Execution
• Enterprise Resource Planning:
– Business Planning & Logistics
– Plant Production Scheduling
– Operational Management, etc.
• Manufacturing Execution System:
– Manufacturing
Operations & Control
– Dispatching Production, Detailed
Product
Scheduling, Reliability
Assurance,...
Supervision (SCADA)
Group Control
Individual
Control
Field
• Control & Command System:
– Batch control
– Continuous Control
– Discrete control
Primary technology
Process Automation
14/27
Example: Siemens WinCC
Process Automation
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Large control system hierarchy
4
Planning, Statistics, Finances
3
Workflow, Resources, Interactions
2
Supervisory
SCADA =
Supervisory Control
And Data Acquisition
administration
enterprise
supervision
Group Control
Unit Control
1
Field
Sensors
& Actors
0
A V
T
Primary technology
Process Automation
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Large control system hierarchy – Cont… 2
• Administration:
– Production goals, planning
• Enterprise:
– Manages resources, workflow, coordinates activities of different sites
quality supervision, maintenance, distribution and planning
• Supervision:
– Supervision of the site, optimization, on-line operations, Control
room, Process Data Base, logging (open loop)
• Group (Area):
– Control of a well-defined part of the plant (closed loop, except for
intervention of an operator)
» Coordinates individual subgroups, Adjusting set-points and parameters
» Commands several units as a whole
Process Automation
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Large control system hierarchy – Cont… 3
• Unit (Cell):
– Control (regulation, monitoring and protection) of a small
part of a group (closed loop except for maintenance)
» Measure: Sampling, scaling, processing, calibration
» Control: regulation, set-points and parameters
» Command: sequencing, protection and interlocking
• Field:
– Sensors & Actuators, data acquisition, digitalization, data
transmission
– No processing except measurement correction and built-in
protection
Process Automation
18/27
Field level
• Field level is in
direct interaction
with the plant's
hardware
Process Automation
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unit controllers
Group level
• Group level coordinates
the activities of several
unit controls
• Distributed Control
Systems (DCS)
commonly refers to a
hardware and software
infrastructure to perform
Process Automation
Process Automation
20/27
Local human interface at group level
Sometimes, the group level has its own
man-machine interface for local operation
control (here: cement packaging)
Process Automation
Maintenance console /
emergency panel
21/27
Supervisory level: Man-machine interface
• Control room (mimic wall) 1970s...
• All instruments were directly wired to the control room
Process Automation
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Supervisory level:
SCADA = Supervisory Control and Data Acquisition
• Displays the current state of
the process (visualization)
• Display the alarms and
events (alarm log, logbook)
• Display the trends
(historians) and analyse
them
• Display handbooks, data
sheets, inventory, expert
system (documentation)
• Allows communication and
data synchronization with
other centres
Process Automation
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Operator workplace: Three main functions
2. Trends and history
1. Current state
3. Alarms
and
events
Process Automation
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Response time and hierarchical level
ERP
Planning
Level
(Enterprise Resource
Planning)
MES
Execution
Level
(Manufacturing
Execution System)
SCADA
(Supervisory Control
and Data Acquisition)
Supervisory
Level
DCS
(Distributed
Control System)
Control
Level
PLC
(Programmable
Logic Controller)
ms
seconds
hours
days
Process Automation
weeks
month
years
25/27
Complexity and Reaction Speed in Hierarchical levels
ERP
MES
Supervision
Group Control
Individual Control
Field
months
days
minutes
seconds
0.1s
0.01s
Site
Complexity
Reaction Speed
Process Automation
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Operation and Process Data
• Normally, the operator
is only concerned by
the supervisory level,
but exceptionally,
operators (and
engineers) want to
access data of the
lowest levels
• The operator sees the
plant through a fast
data base, refreshed in
background
Process Automation
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