engine systems - eth zürich hedinger | 26.09.2016 | 10 air-to-fuel ratio feedback control three way...

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Prof. Chris Onder

Norbert Zsiga

Raffi Hedinger

Michael Zihlmann

26.09.2016Raffi Hedinger 1

Engine Systems

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Chris Onder, Professor

[email protected]

ML K37.2, Tel. 044 632 24 66

Norbert Zsiga, PhD Student

[email protected]

ML K41, Tel. 044 632 25 94

Raffi Hedinger, PhD Student

[email protected]

ML K41, Tel. 044 632 49 39


People

If you have any questions: come and ask!

mailto:[email protected]



|| 26.09.2016Raffi Hedinger 3

Structure

Lectures

Exercises (Practical and Theoretical)

Time and Place Monday, 8:15h-10:00h, ML F 38

Presenter Prof. Onder

Intake Manifold Idle Speed Controller Design Process

Theory Exercises

Time and Place Monday, 12:15h-13:00h, ML H 41.1

Presenters Norbert Zsiga, Raffi Hedinger

Start of Semester End of Semester


Off topic: Fisita Travel Bursary Programme

More information: http://www.fisita.com/education/bursary

Swiss Delegate: Chris Onder

2000 € for ICE

internship abroad

http://www.fisita.com/education/bursary

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Why?

Modeling?

Controls?

How?


Modeling and Control of Internal Combustion

Engine Systems

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1943: Beginning of huge smog problems in Los Angeles

1950: Caltech researchers identify problem: unburned hydrocarbons in the air

1956: US Clean Air Act

1975: Catalytic converters are mandatory equipment for cars in the US


The Birth Hour of Modern Engine Controls


Catalytic Converters

Emissions

Unburned hydrocarbons (𝐻𝐶)Nitrogen Oxides (𝑁𝑂,𝑁𝑂2: 𝑁𝑂𝑥)Carbon Monoxide (𝐶𝑂)

“Clean Air”

Water 𝐻2𝑂Carbon Dioxide (𝐶𝑂2)Nitrogen (𝑁2)

Perfect

Three Way Catalytic Converter





Smog

Acid rain

Death (0.04%: 3 hrs)

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1.110.9 λ [−]

conversion

efficiency

stoichiometrylean:

too much air

rich:

too much fuel


Catalytic Converters





1976: Bosch presents first air-to-fuel ratio sensor for use in cars

𝜆 =𝑚𝑎𝑖𝑟

𝑚𝑓𝑢𝑒𝑙 ⋅ 𝜎0

𝜎0 = stoichiometricair

fuelratio


Air-to-Fuel Ratio Feedback Control

Three Way Catalytic Converter





1976: Bosch presents first air-to-fuel ratio sensor for use in cars

add more or less

fuel to reach

stoichiometry

feedback

control

loop

air-to-fuel ratio

sensor

Exhaust mass flow


Basic Engine Sensors and Actuators

TWC

Tank

1 2

TWC

throttle

intake

manifold

fuel

pump

injector

spark

plug

air-to-

fuel ratio

sensor

three way

catalyst

piston

air mass

flow meter

knock sensor

engine speed

driver pedal position

Engine Control Unit


Modern Engine Feedback Control

air-to-fuel ratio

sensor 𝐶𝜆injection

duration

• Emissions

• Safety of engine components

• Efficiency?


Engine Efficiency

0.1

0.2

engine efficiency =0.25

0.3

0.330.350.36

engine

torque

engine

speed


Engine Efficiency

0.1

0.2

engine efficiency =0.25

0.3

0.330.350.36

engine

torque

engine

speed

Downsizing

and supercharging


Modern Engine Feedback Control

air-to-fuel ratio


duration

• Emissions

• Safety of engine components

• Efficiency?

• Desired load torque

• Knocking

• Center of combustion

• Boost pressure

• EGR rate

• Valve timing

• Fuel pump

• Water pump

• ...

driver pedal position

Engine Control Unit


Not Combustion Related Control Systems in

Current Cars

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Why?

Modeling?

Controls?

How?



Engine Systems


Best Possible Model Based Controller Designdriver pedal position

Engine Control Unit

TWC

Tank

1 2

TWC

throttle

intake

manifold

fuel

pump

injector

spark

plug

air-to-

fuel ratio

sensor

three way

catalyst

piston

air mass

flow meter

knock sensor

engine speed


Best Possible Model Based Controller Design

TWC

Tank

1 2

TWC

injector

air-to-

fuel ratio

sensor



𝑇90

𝜆 signal, instantaneous fuel mass decrease at 𝑡 = 0

Time

𝑡 = 0

𝛥𝑡



𝛥𝑡

𝑇90𝑇90

Time

𝑡 = 0

𝛥𝑡




𝛥𝑡

𝑇90𝑇90

Time

𝑡 = 0

𝛥𝑡

Internal Model

Controller𝜆

Δ𝑡, 𝑇90

Controller

Output

ctrl. speed



Standard Model Based Controller Design

Procedure

1. Create physically based mathematical model

2. Get engine running

3. Take measurements for identification and validation

4. Use model to design and tune controller

Benefits of physically based model

1. Theoretical stability analysis is possible

2. Offline controller tuning

3. Model-based optimal control

4. Can be used for other engines, too

5. Model can be used for feedforward control

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Why?

Modeling?

Controls?

How?



Engine Systems

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Objectives

Understanding of physical processes in

engines

Derive simplified models suited for model-

based control

Content

Mathematical models of most important

engine components (continuous time)

Discrete event models (discrete time)

Controller design case studies


The Lecture

80% Modeling 20% Control


The Lecture

# Content

0 Extra Introductory Lecture

1 Introduction, Goals, Administration, Examples

2 Models I: Causality Diagrams, Air Path

3 Models II: Air path, Fuel path, A/F dynamics

4 Models III: Torque Production

5 Test Benches, Sensors, Actuators

6 Models IV: Thermal Models

7 Models V: Emissions, TWC

8 Models VI: Emissions, SCR

9

Models VII: Discrete Event Modeling, Introduction, Crank-angle Based Modeling, Hardware,

Interpretation of Measurements, Torque production, Air Mass Estimation, Fuel Path, Exhaust Gas

Mixing, EGR-Model

10 Guest Speaker

11 Modern Engine Control Units, Torque Based Structure, A/F Control: Feedforward Evaluation

12 A/F control: Feedback: Switch-Type Control, Wide Range Control, MIMO-Control, Evaluation

13 SCR Control, Thermomanagement Control


The Lecture


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Objectives

Apply knowledge from the lecture

Content, theoretical part

Gain better understanding of the

theory from the lecture

Content, practical part

Design model based idle-speed

for a 5-cylinder engine

Take your own measurements on

the test bench

Competition at end of semester


The Exercises


The Exercises


Idle Speed Control Problemdriver pedal position

Engine Control Unit

TWC

Tank

1 2

TWC

throttle

intake

manifold

fuel

pump

injector

spark

plug

air-to-

fuel ratio

sensor

three way

catalyst

piston

air mass

flow meter

knock sensor

engine speed


Idle Speed Control Problem

air-to-fuel ratio


duration

Engine speed 𝐶𝑀𝐼𝑆𝑂injection duration

ignition timing

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Why?

Modeling?

Controls?

How?



Engine Systems


Structure

Lectures

Exercises (Practical and Theoretical)

Time and Place Monday, 8:15h-10:00h, ML F 38

Presenter Prof. Onder

Intake Manifold Idle Speed Controller Design

Theory Exercises

Time and Place Monday, 12:15h-13:00h, ML H 41.1

Presenters Norbert Zsiga, Raffi Hedinger

Start of Semester End of Semester

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General

Class facts sheet online

Class text book will be distributed as .pdf file

Oral exam, 30min, during examination session

Exercises

Work in groups of 4 people

Exercise instruction script available online

Controller performance competition at end of semester

Win pizza voucher

Exercises are not mandatory


Useful Information

engine systems - eth zürich hedinger | 26.09.2016 | 10 air-to-fuel ratio feedback control three way...

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