1.5 Control System Architecture
Transcript of 1.5 Control System Architecture
1.5 Control System Architecture3Industrial Automation
Principle
The control system has to suit the plant, not the reverse
The structure of the control system should reflects that of the plant
Ideally, each unit of the plant should have its own controller,
interacting with the controllers of the other, related units,
mirroring their physical interaction.
Example: Airbus: a wing is delivered with its own computers.
1.5 Control System Architecture6Industrial Automation
Example: Production management system
transportation
cell control
manufacturing
cell control
scheduling maintenance quality control
plant network
floor network
production
planning
robot
controller
enterprise network
milling
machine
rail-guided
vehicle
cell
1.5 Control System Architecture7Industrial Automation
Example: Power plant control - 1980 (!)
Control systems look similar
1.5 Control System Architecture9Industrial Automation
Example: Rockwell (Allen-Bradley) NetLinx
Modular
I/O
HMI
24vdc
509 -BOD
Bridge or Linking Device
Programmable
Device
Support PC
Block I/O
Micro
PLC
Drive
Servo
Controller and Bridge
HMI
Desktop PC
with excel
Linking Device
Sensor
EtherNet / IP
ControlNet
DeviceNet
1.5 Control System Architecture11Industrial Automation
Example: ABB Industrial IT (redundant system)
3rd party
controllers,
servers etc
Serial, OPC
or fieldbus
engineering
workplace
Field Bus
Firewall
Plant Network / Intranet
Field Bus
Client/server Network
3rd party
application
server
application
server
aspect
server
Workplaces
(clients)
Enterprise
Optimization
(clients)
Mobile
Operator
connectivity
server
Control Network
Programmable
Logic Controller
AC 800CRedundant
AC 800M
touch-screen
1.5 Control System Architecture15Industrial Automation
Centralized Control Architecture (classical)
Sensors, Actors
PLCsGroup
Control
Group
Control
Group
Control
Central Computer
(Mainframe)
Classical, hierarchical, centralized architecture.
The central computer only monitors and forwards commands to the PLCs
plant
1.5 Control System Architecture16Industrial Automation
plant
Decentralized Control System (DCS)
engineering
workstation
operator
workstationdata logger
controller controller controller controller
field bus
plant bus
all controllers can communicate as peers (without going through a central master),
restricted only by throughput and modularity considerations.
Note: Honeywell's "DCS™" stands for "Distributed Control System", it is not a decentralized control system, but
a control system for the process industry.
peer-to-peer (horizontal communication)hierarchical
(vertical
communication)