using physical modeling tools to design power optimized ... · technical marketing, physical...
TRANSCRIPT
©20
08 T
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Steve Miller
Technical Marketing, Physical Modeling Tools
The MathWorks GmbH, Munich, Germany
Using Physical Modeling Tools to Design Power Optimized Aircraft
Actuator Force
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Key Points
1. Testing different actuatordesigns in one environmentsaves time and encouragesinnovation
2. Optimizing systems with respectto design requirements leads to optimal design choices
3. Simulating at different levels of fidelity is required to see effectsof design implementation
Actuator ForceAileron Angle
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AgendaTrends in the aerospace industry 10 min
Industry trendsStrategies for improvementHow simulation can help
Example: Flight Actuation System 15 minModel explanationTradeoff studySystem optimizationAssess implementation effects
Conclusions
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Industry Trends
System needsAircraft must produce less pollutionAircraft must be more efficient
Example goalsClean Sky (for year 2020)
50% reduction of CO2 emissions80% reduction of nitrous oxide emissions
Power Optimized Aircraft (POA)25% cut in peak non-propulsive power5% reduction in fuel consumption
Strategies include aircraft-level optimization, technology
“With 5-6°C warming … existing models … estimate an average
5-10% loss in global GDP.”
“With 5-6°C warming … existing models … estimate an average
5-10% loss in global GDP.”
Head of the Government Economic ServiceUK, 2006
Research project, EU and industry
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Strategies for Improved Aircraft Design
Technology: Electrical actuationFewer losses than hydraulic actuationOnly needs to be turned on when in useTend to be more reliable, cleaner, and safer
Aircraft-level optimizationConsolidation of power electronicsLocalize hydraulic actuation
Simulation can help with each of these strategies
Boeing 787 Electrical Systems
BrakesIce protectionEngine start
Environmental controls Electrohydraulic pumps
Boeing 787 Electrical Systems
BrakesIce protectionEngine start
Environmental controls Electrohydraulic pumps
Airbus 380Electrical Systems
Primary flight control actuatorsThrust reverser actuation
Horizontal stabilizer backup
Airbus 380Electrical Systems
Primary flight control actuatorsThrust reverser actuation
Horizontal stabilizer backup
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How Simulation Can Help
1. Tradeoff studies to test electrical and hydraulic systemsDetermine actuator requirementsTest hydraulic and electrical actuator designs
2. System-level modelsMust be done at aircraft level to optimize architectureFew key parameters and quick simulation
3. Simulating at different levels of fidelityNeed to easily add fidelity to see impacts of implementationReuse work done at system level (Model-Based Design)
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Example: Aileron Actuation System
System
Simulation goals1. Determine requirements for actuation system2. Test performance with electrical or hydraulic actuation3. Optimize the actuation system4. Assess effects of system implementation
Control Actuation
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Determining Actuation Requirements
Problem: Determine the requirements for an aircraft aileron actuator
Solution: Use SimMechanics™ to model the aileron and Simscape™to model an ideal actuator
Model:
IdealActuator
θAileron
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Test Electrical and Hydraulic Designs
Problem: Test different actuator designs in the systemSolution: Use SimHydraulics®
and Simscape to model the actuators, and configurable subsystems to exchange them
Model:
Electro-mechanical
Hydraulic
Actuator
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Actuator System-Level Designs
Hydrostatic transmission
Variable-displacement pump Double-acting hydraulic cylinderReplenishing valvesPressure-relief valvesCharge pumpSpeed controller
Electromechanical system
DC MotorWorm gearCurrent sensorand current controllerHall effect sensorand speed controller
SpeedControl
CurrentControl
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Optimize System Performance
Problem: Optimize the speed controller to meet system requirementsSolution: Use Simulink® Response Optimization™ to tune the controller parameters
Model:
ω
Angle
Current
Kp Ki
0.3 0.3
CurrentControl
SpeedControl
i
ωSpeed
Control
Kp Ki
23.4 3.67
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Assess Implementation Effects
Problem: Assess the effects of design implementation on system performanceSolution: Use Simscape to add a the analog circuit implementation
Model: Current
CurrentControlSpeed
Control
ωi
1s
Simulink Circuit
ω i
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Conclusion1. Testing different actuator
designs in one environmentsaves time and encouragesinnovation
2. Optimizing systems with respectto design requirements leads to optimal design choices
3. Simulating at different levels of fidelity is required to see effectsof design implementation
Actuator ForceAileron Angle
14
® ®
MathWorks Products Used
SimscapeMultidomain physical systems
SimMechanics3-D mechanical systems
SimHydraulicsHydraulic (fluid power) systems
Simulink Response Optimization
MATLAB, Simulink
Sim
Pow
erSy
stem
sTM
Simscape
Sim
Mec
hani
cs
Sim
Driv
elin
e
Sim
Hyd
raul
ics