automotive powertrain controls: fundamentals and frontierscset.mnsu.edu/tcac/acc05_jcook2.pdf · 3...
TRANSCRIPT
12005 American Control Conference
June 8-10, 2005, Portland, OR.
Automotive PowertrainControls: Fundamentals and Frontiers
Jing SunDepartment of Naval Architecture and Marine Engineering
University of MichiganAnn Arbor, MI USA
Julie BucklandResearch & Advanced Engineering
Ford Motor CompanyDearborn, MI USA
22005 American Control Conference
June 8-10, 2005, Portland, OR.
TopicsModeling and Control of Automotive Powertrain Systems: A Tutorial, Jing Sun (UM), Ilya Kolmanovskyand Jeff Cook (Ford Motor Company)Challenges and Opportunities in Automotive Transmission Control, Zongxuan Sun and Kumar Hebbale, General Motors Corp. Automotive Emissions Control, Julia Buckland and Jeff Cook, Ford Motor Company Towards a Concurrent Engine System Design Methodology, Akira Ohata and Ken Butts, Toyota Motor Corp.
32005 American Control Conference
June 8-10, 2005, Portland, OR.
Modeling and Control of Automotive Powertrain Systems
Introduction and motivation: Models, methods and issues (Jeffrey Cook)Gasoline direct injection engine control (Jing sun)Diesel engine control (Ilya kolmanovsky)
42005 American Control Conference
June 8-10, 2005, Portland, OR.
History: Electronic Powertrain Controls
Emissions-driven technology development1980s: Decade of controls1990s: Decade of systems2000s: Complexity and sustainable mobility
52005 American Control Conference
June 8-10, 2005, Portland, OR.
Constraints: Fuel Economy and Performance
Europe: 140 g/km CO2 by 2008 (25% reduction compared to 1995 baseline)US (Federal): 27.5 mpg CAFEUS (California): Air Resources Board to write rules curbing carbon dioxide and methane emissions starting with the 2009 model yearEverywhere: Customers
72005 American Control Conference
June 8-10, 2005, Portland, OR.
Sensors and Actuators
Powertrain controller32-bit MPC55xx, ~150 pin I/O connector; ~90 control features
SensorsAir flowExhaust O2 or A/F (2-3 places)Intake manifold pressureCrankshaft and camshaft position (engine speed)Throttle positionFuel rail pressureEGR position or delta PressureKnock (accelerometer)
SensorsTemperature (air, intake and exhaust manifold, engine coolant, catalyst bed)Accessory loads (A/C clutch compressor sensor, battery voltage, power steering pump)Potentially ionization, in-cylinder pressure, emissions sensors (NOx)
82005 American Control Conference
June 8-10, 2005, Portland, OR.
Sensors and Actuators
ActuatorsThrottleAir bypass valveFuel (pump, pressure regulator, injector timing and duration),IgnitionEGRCamshaft phase (intake and/or exhaust)WastegateSecondary airCanister purgeCharge motion controlIntake manifold tuning
Actuators (potentially)Valve lift, Cam profile switchingElectronic valve actuationCylinder deactivationVGTVariable compression ratioIntegrated starter-alternator Clutched superchargerTraction motor
92005 American Control Conference
June 8-10, 2005, Portland, OR.
ThrottleIntake manifold dynamicsEngine pumping and intake valve flowTorque generationRotational Dynamics
Basic Engine Model
Exhaust manifold dynamicsAir and fuel path delaysFeedgas emissionsTWC (including dynamics)Sensor and actuator dynamics (throttle, VCT, turbocharger, etc.)
102005 American Control Conference
June 8-10, 2005, Portland, OR.
Basic Engine Model
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Manifold Pressure
Flow Equations
Cylinder Air Charge
Torque and Rotational Dynamics
112005 American Control Conference
June 8-10, 2005, Portland, OR.
Conventional Aftertreatment Systems
“Three-way” catalytic converterNarrow “window” of high simultaneous conversion efficiencyConventional control objective is to regulate A/F to stoichiometry
122005 American Control Conference
June 8-10, 2005, Portland, OR.
HEGO Sensor
Potentiometric Electrochemical sensorElectric potential related to oxygen partial pressureStandard on all US vehicles since 1980Essentially a switch
132005 American Control Conference
June 8-10, 2005, Portland, OR.
UEGO Sensor
Switching-type sensor with additional electronicsAmperometric sensor measures current proportional to oxygen partial pressure (lean) or hydrocarbon partial pressure (rich)
142005 American Control Conference
June 8-10, 2005, Portland, OR.
Closed-loop A/F Control
Estimate cylinder air charge (including EGR)Schedule fuel to achieve stoichiometry Use HEGO/UEGO feedback to compensate for uncertainties
But …Accuracy in air charge estimationTransient fuel dynamicsLimited feedback information when using HEGOTransport delayInjector variabilitySensor variabilityDisturbance inputs(vapor purge)
152005 American Control Conference
June 8-10, 2005, Portland, OR.
Transient Fuel Dynamics
Not all fuel injected gets into the cylinderSome fuel stays in the intake port and forms a puddle on the wall Fuel from puddle inducted in subsequent fueling events, causing AFR transient
162005 American Control Conference
June 8-10, 2005, Portland, OR.
Electronic Throttle Control
Inner-loop control: move the mechanical plate to the desired positionOuter-loop control: to command the ETC position to provide the desired air flow
But …Inner loop:
Highly nonlinear with significant friction and hysteresisResolution requirements at closed throttleChoked flow is sensitive to ambient pressure
Outer loop:Inverse orifice equation for throttle position control is almost singular at WOT
172005 American Control Conference
June 8-10, 2005, Portland, OR.
Other Powertrain Control Problems
Idle speed controlVariable cam controlEGRAir charge estimationShift scheduling and controlEvaporative emissions controlIgnition controlCold start controlsCatalyst temperature controlTorque control (electronic throttle)
Fuel pressure controlMisfire detectionCatalyst diagnosticsCruise controlTurbo/supercharger controlKnock detectionMisfire detectionSecondary air controlCylinder deactivationTorque converter lock-upFlex/fringe fuel detection