Industrial Automation: Situation and Trends
Transcript of Industrial Automation: Situation and Trends
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Industrial Automation:Situation and Trends
IFAC 50th AnniversaryHeidelbergSeptember 15, 2006
Peter TerwieschChief Technology Officer
ABB
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6Overview
� Industry needs
� A visual history of industrial automation system evolution
� Industrial application examples
� Summary and outlook
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6Industry Needs
Global competition: � Improve
productivity� Deliver flexibly,
better, more …
� … with less: economically, and ecologically
� Focus capital spending,improve asset utilization
Time
Throughput
Lost opportunity
Plant upset
Startup
Partial shut-down
Design limit
Loss
Pro
fit
Shut-down
Break Even
Operatingtarget
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New technology enables ...• Standard Communications• The ability to interact with a device and know
the process better• Distributed intelligence• Reduced cost per function
Time
Func
tiona
lity
Fieldbus
Fieldbus
More valuesMulti variable
High resolutionDiagnostic dataQuality signal
Status De-central FunctionsDistributed Control
Bi-directional Asset Optimization
Graphics
SMART
HART
ValueDevice
Parameter
4-20mA
Traditional
Value
Advanced diagnostics
and Asset management +
multi systems in
tegration
Intelligent Field Devices
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6Automation Industry Consolidation
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6IT: Challenge and Opportunity
Customizedsolutions
Standardizedproducts
Build on fastdevelopment in
IT and electronics
Well-proven technology and 15-20 years life time
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6Process trends: increased integration
Process buffers at all levels get trimmed: supply chain, company, site, plant, unit
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6Process trends: tightening constraints
$$$
$$
Constraints and boundaries tighten, consequences of violation
become increasingly severe
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6Trend: broader scope, more complex models
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� 620,000 ton� Three fiber lines� Six paper machines
� 620,000 ton� Three fiber lines� Six paper machines
ContainerboardSackKraftMarket pulp
Trend: broader scope, more complex models
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Example:Pulp Mill
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61960s: Production optimization at Gruvön in
� Licentiate thesis by Bengt Pettersson
� Figures courtesy of Karl Johan Åström
Example:Pulp Mill
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25 Production units38 Buffer tanks250 Streams250 Measurements2500 Variables
Example:Pulp Mill
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State EstimationOptimization
Simulation
Each cycle approx. 30 minutes
On-line operationExample:Pulp Mill
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Configuration of a heat recovery steam generation plant
Superheatersubsystems
NMPC: Minimizing Thermal Stress at Boiler Start-up
Thick-walled steam header (cylindric type, 6.4 cm thick)
Stretching of the material because of temperature gradients lead to lifetime reduction
Example:Boiler Startup
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6Exemplary Water-Steam Cycle
SPW-Druck vor HD-VorwärmerRL10P002
HD-Vorwärmer
Verdampfer
SPW-PumpeEco
Abscheider4
EK I/1EK I/2
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pD Anfahrflasche NB01P003
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Temp Speisew vor ECORL15T004
ECO Speisew.-Menge RL15F001
Niveau AnfahrflascheNB01L901
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EK IV/4
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Example:Boiler Startup
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6Object-oriented modeling
� Graphical flowsheet modeling
� Combine commodity models with proprietary knowledge
� Automatic generation of stand-alone executable code
Example:Boiler Startup
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6Dynamic optimization problem
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� Process model
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Example:Boiler Startup
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6Solution Approach
� Parameterize control u(t) = u(uk), k=0,1,…,K-1
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Example:Boiler Startup
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6Organizing Information With Aspect ObjectsTM
AspectObject
Aspects
RealObject
Aspect Systems
Inventory reportMicrosoft
Excel
MicrosoftWord
SAP, IFS . . .
Dynamic Optimization
Operationalprocedure
Productionschedule
Productspecification
MechanicalDrawing
TransitionOptimization
AutoCAD
Example:Boiler Startup
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6NMPC Integration with Control System
NMPC with 800xA� Seamless integration with
operator station � Data serving (Aspect
Server, Basic History)� Connectivity to process
databases� Connectivity to major
control systems� Further synergies,
e.g. alarm handling
Example:Boiler Startup
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6Conventional ramp start-up
� Classical start-up: apply ramp on fuel flow rate q_F
� Thermal stress violates constraint (-60 instead of –25)
Example:Boiler Startup
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6Optimized start-up
� Result: achieve faster startup and fulfill constraints
� Seamless integration with Trend&Historian subsystem
Example:Boiler Startup
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6Thickness Control in Cold Rolling Mills
� Conventional control:� Single control loops
� Feed forward strategies
� Limited performance
� Task and objectives:� Improve tolerance over
the whole strip length
� Improve quality during ramp-up / ramp-down
� Better disturbance rejection to allow higher speed
Roll position
Uncoiler torque
Coiler torque
Output thickness
Uncoiler tension
Coiler tension
Input thickness
Rolling stand
Roll position
Uncoiler torque
Coiler torque
Output thickness
Uncoiler tension
Coiler tension
Input thickness
Rolling stand
Example:Cold Rolling
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6New Advanced Thickness Control
Dynamically decoupled MIMO control with� Online estimation of time
varying process parameters
� Online MIMO controller parameter adaptation using an in-built process model
� Dynamic feed-forward strategies support disturbance rejection
� Supervision layer to monitor and track the control quality
Pass schedule, Set-up and adaptation
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DynamicDisturbance FF
Parameters
Pass schedule, Set-up and adaptation
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Controllerdesign/adaption
On-line PlantModel
On-lineEstimation
Controllerparameter
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PIDs DynamicDecoupler
DynamicDisturbance FF
Parameters
Example:Cold Rolling
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Conventional control: h0 = 575µm, h1 = 400µm, width = 1244mmAdvanced control: h0 = 575µm, h1 = 400µm, width = 1285mm
Conventional control• Standard deviation:
• Body 3σ = 1,18%• Total 3σ = 1,32%
Conventional control• Standard deviation:
• Body 3σ = 1,18%• Total 3σ = 1,32%
Comparison: Conventional vs Advanced
New Advanced Control• Standard deviation:
• Body 3σ = 0,49%• Total 3σ = 0,66%
New Advanced Control• Standard deviation:
• Body 3σ = 0,49%• Total 3σ = 0,66%
Example:Cold Rolling
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Recent innovations:� Multi-move: robots that collaborate� Force control: robots that feel� Vision: robots that see� Easy programming
Outlook:� More sensors, more sensor fusion� Closer human-robot collaboration
Control: Also at the heart of RoboticsExample:Robotics
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6Economic Process Optimization
� Different control systems, office environment, and enterprise systems can all talk to each other in real time
� Live external data feeds also easily integrated, e.g., spot market prices for feedstock, energy, product, weather information …
� Can we use this information together with modeling and a feedback control approach to online optimize whole plants from an economic perspective?
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6Hybrid: Mixed Logic Dynamic Systems
� Framework for handling continuous and discrete dynamics
� Describes both plant constraints and objective function
� Collaboration with ETH Zürich
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6Grinding Plant Scheduling
Example:Minerals
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6Electrical Energy Management: Benefits
� Power cost down by 2-3%� Automatic rescheduling in case of unexpected events� Strict contractual and equipment constraint satisfaction
Example:Minerals
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6Modeling and model re-use
Control, equipment design optimization
Operating procedure optimization
Many others
Soft sensing
Yield accounting
Decision support
Diagnosis and troubleshooting
Optimization (ss + dynamic)
Linear models
[A,B,C,D]
MPC
Linearized models
Linearization
Advanced MPC
EstimationInitial model
Fitted modelOffline
Plant data
Up-to-date model
Reconciled plant
information
OnlineRaw plant data
Plant
Data Reconciliation Parameter Estimation
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Reference ActuationSensing & Estimation
Context, e.g. market price, weather forecast
EconomicOptimization
Economic life-cycle cost estimate
Life-cycle optimization: The Next Loop?
Control Life-CycleCost ModelProcess
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6Automating automation: The engineering data chain
P&IDFUP...
Offer Process Design Control Design Installation
Outlook
Engineering� Ideally, feed in only process model and objective
� Plant topology from P&ID, economic context from ERP
� Hardware and software components from vendor
� Hardware realization/configuration automatic
� Still a long journey, but economic importance high
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6Other open frontiers
� Methods� Bring mathematical assumptions and physical reality closer together
� extend hybrid optimizers to larger problem sizes� guaranteed properties for real-world closed-loop systems?
� Robustness of solvers towards unsupervised closed-loop operation� Dealing with significantly different time horizons
(asset dynamics tend to be much slower than process dynamics, e.g., wear, corrosion, crack propagation)
� Problem solving� Deal with abnormal, unexpected, situations
(e.g., interruption of communication, or alarm bursts etc) � Deal more readily with changing constraints
and changing configurations� Exploit distributed problem-solving capabilities
� distributed problem solving, e.g., agent approaches?� gain flexibility, but loose predictability? system properties?
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6Summary and Acknowledgments
Summary
� Control system capability ceases to be the active constraint regarding computing power, memory, flexibility, and ease of interfacing
� Is the theory-practice gap narrowing?
Acknowledgments
� To customers, colleagues and university partners for sharing their insights
� R. Franke, A. Vollmer, A. Isaksson, E. Gallestey for providing examples
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