Load measurement of substances on SCR, GPF, TWC through radio frequency analysis. Machine learning for compensation of cross sensitivities.

1. RF Antenna for SCR, TWC, GPF
Machine Learning for Load
Measurement
6th International Conference Aftertreatment & Sensors
Marco Moser, Munich, September 2019

2. Content
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors2
 Update RF Antenna
 Controls
 OBD
 Exhaust Gas After
Treatment Components
 SCR Control with
Extended Kalman Filter

3. Motivation
Correct SCR Load Determination
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors3
 High potential of RF antenna for SCR load determination
DOC SCRDPF
SCR model
Engine
NOX
NH3
NH3 load
Current Situation:
NH3 load modelled
complex  miscalculation 
emissions
New RF (Microwave) Sensor:
NH3 load measured
direct measurement
NH3 load
Diesel

4. Amplitudedamping
[dB]
-14
-13
-12
-11
-10
RF model 0g
RF model 2g
RF signal
SCRNH3load
[g]
0.5
1.0
1.5
2.0
Target load
ECU model load
NH3masserror
[g]
0
1
2
Time [s]
0 200 400 600 800 1000
ECU miscalculation
RF corrections acummulated
SCR Load Control - NH3 Dosing Control
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors4
 Implemented closed-loop control capable to compensate different errors without causing additional emission
Continuous error is corrected
visibly (saw teeth)
Time raster through filtering of
sensor signal
RF correction value corresponding
to ECU miscalculation
Example Road Measurement
Correction of calculated NH3 load

5. Machine Learning Approach - RF Signal with ML
Compensation
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors5
 Easy way for compensating cross influences in RF signal to get exact NH3 load measurement

6. Stationary Tests - SCR Ageing: New, FUL, EOL
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors6
TSCR = 255°C
AdBlue®
dosing start dosing stop
empty
 Amplitude damping shows effects of aged SCR: deterioration of storage capacity
difference from
stored humidity
difference from
stored humidity +
NH3
NEW
FUL
EOL

7. Transient Tests - SCR Ageing: FUL, EOL
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors7
 With cross-influence-compensated RF signal it is possible to detect ageing of SCR
FUL ageing
EOL ageing
start with empty SCR
RF signal correlates
with:
- NH3 load
- Humidity
- Temperature
- Ageing

8. Challenges in TWC Control
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors8
TWC performance depending on oxygen storage level
Upcoming challenges:
• Limited NH3 emissions (NH3 emitted under rich
conditions)
• Today’s applications: slightly rich operated engine,
TWC fully oxidized in fuel cuts
• Hybrid gasoline vehicles: no more fuel cut
New operation strategy requires new sensor?
 RF advantages for TWC oxidation control
Sensor signal dependency on HC exhaust composition
RF Sensor advantage:
• Sensor is directly measuring the oxygen storage level
and not by indirect means
Optimal conversion
Lambda probe not
able to detect
oxidation state
RF able to detect
50% conversion

9. GPF Soot Loading Determination – RF Sensor Performance
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors9
Soot loading operation point
and temperature variation
Cold start sensor signal
0 0.5 1 1.5 2 2.5
time / s 10
4
0
1
2
3
4
m
soot
/g
soot loading and temperature variation
soot load reference
soot load from RF
0 0.5 1 1.5 2 2.5
time / s 10
4
0
200
400
600
800
torque/Nm/T/°C
0.8
1
1.2
1.4
1.6
NOx-Sensor
torque / Nm T / °C lambda
0 500 1000 1500
time / s
0
1
2
3
4
m
soot
/g
cold start with 2,25 g soot load
soot load reference
soot load from RF
0 500 1000 1500
time / s
0
200
400
600
torque/Nm/T/°C
0.8
1
1.2
1.4
1.6
NOx-Sensor
torque / Nm
T / °C
lambda
0 200 400 600 800 1000 1200
time / s
0
1
2
3
4
m
soot
/g
RDE with 3,35 g soot load
soot load reference
soot load from RF
0 200 400 600 800 1000 1200
time / s
0
100
200
300
400
torque/Nm/T/°C
0.8
1
1.2
1.4
1.6
NOx-Sensor
torque / Nm
T / °C
lambda
RDE test cycle with preloaded GPF
RF sensor advantage for GPF load determination:
• High soot load accuracy, temperature compensation as main influence, decreased accuracy at high transients
• Capability to measure in all states: cold start, engine off, operation
 RF antenna as missing link to GPF control and OBD

10. Content
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors10
 Update RF Antenna
 Controls
 OBD
 Exhaust Gas After
Treatment Components
 SCR Control with
Extended Kalman Filter

11. AECC Demonstrator Car (aecc.eu)
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors11
 RF antennas integrated in demo car

12. AECC Demonstrator Car - Layout
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors12
Low & High Pressure EGR to reduce engine-out emissions
LNT + dual-SCR to cover wide range of driving conditions
• City driving: close-coupled LNT + SCR and SCR integrated on DPF (SDPF)
• Motorway driving: underfloor SCR and Ammonia Slip Catalyst (ASC)
 Layout consisting of close-coupled and underfloor components cover a wide range of temperatures

13. AECC Demonstrator Car – Tailpipe Emissions
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors13
All measurements
far below emission
limits

14. Content
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors14
 Update RF Antenna
 Controls
 OBD
 Exhaust Gas After
Treatment Components
 SCR Control with
Extended Kalman Filter

15. Extended Kalman Filter for SCR Dosing Control  AECC Demo Car
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors15
 If NH3 slip is detected, the NH3 load gets
corrected only in the right direction
necessary for a full loaded SCR
 Over dosing and high NH3 slip is avoided
𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁,𝑑𝑑𝑑𝑑𝑑 + 1.15 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑑𝑑𝑑𝑑𝑑
SCRF SCR
𝑐𝑐𝑁𝑁𝑁𝑁𝑥𝑥,𝑢𝑢𝑢𝑢
LDM
SCRF
𝑐𝑐𝑁𝑁𝑁𝑁3,1
𝑚𝑚𝑁𝑁𝑁𝑁3,𝑠𝑠,1
𝑐𝑐𝑁𝑁𝑁𝑁𝑥𝑥,1
̇𝑚𝑚𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 𝐴𝐴𝐴𝐴,1
ECU
signals
LDM
SCR
𝑐𝑐𝑁𝑁𝑁𝑁3,2
𝑚𝑚𝑁𝑁𝑁𝑁3,𝑠𝑠,2
𝑐𝑐𝑁𝑁𝑁𝑁𝑥𝑥,2
NH3 load
control
𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁,𝑑𝑑𝑑𝑑𝑑 + 1.15 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑑𝑑𝑑𝑑𝑑
NOx
sensor us
NOx
sensor ds 2
AdBlue
injector 1
EKF 1
Dosing Control with NH3-slip Recognition
EKF 2
Model based dosing software
with NH3 slip recognition
NOx
sensor ds 1
𝑚𝑚𝑁𝑁𝑁𝑁3,𝑠𝑠,1
𝑚𝑚𝑁𝑁𝑁𝑁3,𝑠𝑠,2
NH3 slip
recognition
SCRF
𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 𝑦𝑦𝑦𝑦𝑦𝑦 /𝑛𝑛𝑛𝑛
NH3 slip
recognition
SCR
𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 𝑦𝑦𝑦𝑦𝑦𝑦 /𝑛𝑛𝑛𝑛
Low dimensional
SCR models
EKFs for model
load correction
NH3 slip recognition uses only NOX
sensor signals and is based on a
correlation approach

16. Low Dimensional Model - IAV-Software
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors16
Aim: Creation of a model capable of running on a standard ECU while modelling all relevant mechanisms of a SCR
Reaction Rates: Modelled Reaction Rates:
̇𝑟𝑟𝑎𝑎𝑎𝑎𝑎𝑎 = 𝑘𝑘0,𝑎𝑎𝑎𝑎𝑎𝑎 exp −𝐸𝐸𝑎𝑎𝑎𝑎𝑎𝑎/(𝑅𝑅 𝑇𝑇𝑜𝑜𝑜𝑜𝑜𝑜) 1 − 𝜃𝜃 𝑐𝑐𝑁𝑁𝑁𝑁𝑁  NH3 adsorption
̇𝑟𝑟𝑑𝑑𝑑𝑑𝑑𝑑 = 𝑘𝑘0,𝑑𝑑𝑑𝑑𝑑𝑑 exp −𝐸𝐸0,𝑑𝑑𝑑𝑑𝑑𝑑(1 − Ω 𝜃𝜃)/(𝑅𝑅𝑇𝑇𝑜𝑜𝑜𝑜𝑜𝑜) 𝜃𝜃  NH3 desorption
̇𝑟𝑟𝑁𝑁𝑁𝑁 = 𝑘𝑘0,𝑁𝑁𝑁𝑁 exp −𝐸𝐸𝑁𝑁𝑁𝑁/(𝑅𝑅�𝑇𝑇𝑆𝑆𝑆𝑆𝑆𝑆) 𝑐𝑐𝑁𝑁𝑁𝑁3,𝑠𝑠 𝑐𝑐𝑁𝑁𝑁𝑁  Standard SCR (reduction of NO)
̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁𝑁 = 𝑘𝑘0,𝑁𝑁𝑁𝑁𝑁𝑁 exp −𝐸𝐸𝑁𝑁𝑁𝑁𝑁𝑁/(𝑅𝑅�𝑇𝑇𝑆𝑆𝑆𝑆𝑆𝑆) 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑠𝑠 𝑐𝑐𝑁𝑁𝑁𝑁 𝑐𝑐𝑁𝑁𝑁𝑁𝑁  Fast SCR (reduction of NO, NO2)
̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁 = 𝑘𝑘0,𝑁𝑁𝑁𝑁𝑁 exp −𝐸𝐸𝑁𝑁𝑁𝑁𝑁/(𝑅𝑅�𝑇𝑇𝑆𝑆𝑆𝑆𝑆𝑆) 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑠𝑠 𝑐𝑐𝑁𝑁𝑁𝑁𝑁  Slow SCR (reduction of NO2)
̇𝑟𝑟𝑂𝑂𝑂𝑂 = 𝑘𝑘0,𝑂𝑂𝑂𝑂 exp −𝐸𝐸𝑂𝑂𝑂𝑂/(𝑅𝑅�𝑇𝑇𝑆𝑆𝑆𝑆𝑆𝑆) 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑠𝑠  Oxidation of adsorbed NH3
Equations:
1)
𝑑𝑑𝑐𝑐 𝑁𝑁𝑁𝑁𝑁,𝑠𝑠
𝑑𝑑𝑑𝑑
= ̇𝑟𝑟𝑎𝑎𝑎𝑎𝑎𝑎 − ̇𝑟𝑟𝑑𝑑𝑑𝑑𝑑𝑑 − ̇𝑟𝑟𝑁𝑁𝑁𝑁 − ̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁𝑁 − ̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁 − ̇𝑟𝑟𝑂𝑂𝑂𝑂
2)
𝑑𝑑𝑓𝑓𝑖𝑖 𝑖𝑖𝑖𝑖
𝑑𝑑𝑑𝑑
= 0
3)
𝑑𝑑𝑐𝑐 𝑁𝑁𝑁𝑁𝑁
𝑑𝑑𝑑𝑑
= 0 = 𝑣𝑣𝑠𝑠 𝑓𝑓𝑖𝑖 𝑖𝑖𝑖𝑖 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑖𝑖 𝑖𝑖 − 𝑐𝑐𝑁𝑁𝑁𝑁𝑁 − ̇𝑟𝑟𝑎𝑎𝑎𝑎𝑎𝑎 + ̇𝑟𝑟𝑑𝑑𝑑𝑑𝑑𝑑
4)
𝑑𝑑𝑐𝑐 𝑁𝑁𝑁𝑁
𝑑𝑑𝑑𝑑
= 0 = 𝑣𝑣𝑠𝑠 𝑐𝑐𝑁𝑁𝑁𝑁,𝑖𝑖 𝑖𝑖 − 𝑐𝑐𝑁𝑁𝑁𝑁 − ̇𝑟𝑟𝑁𝑁𝑁𝑁 − 0.5 ̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁𝑁
5)
𝑑𝑑𝑐𝑐 𝑁𝑁𝑁𝑁𝑁
𝑑𝑑𝑑𝑑
= 0 = 𝑣𝑣𝑠𝑠 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑖𝑖 𝑖𝑖 − 𝑐𝑐𝑁𝑁𝑁𝑁𝑁 − 0.75 ̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁 − 0.5 ̇𝑟𝑟𝑁𝑁𝑁𝑁𝑁𝑁
𝑐𝑐𝑖𝑖,𝑖𝑖 𝑖𝑖
𝑐𝑐𝑋𝑋
𝑐𝑐𝑖𝑖,𝑜𝑜𝑜𝑜𝑜𝑜 = 𝑐𝑐𝑖𝑖
with: 𝜃𝜃 =
𝑛𝑛 𝑁𝑁𝑁𝑁𝑁,𝑠𝑠
𝑛𝑛 𝑁𝑁𝑁𝑁𝑁,𝑠𝑠,𝑚𝑚𝑚𝑚𝑚𝑚
, 𝑣𝑣𝑠𝑠 = ̇𝑉𝑉/(𝑉𝑉𝑆𝑆𝑆𝑆𝑆𝑆 𝜀𝜀), �𝑇𝑇𝑆𝑆𝑆𝑆𝑆𝑆 = 𝑓𝑓(𝑇𝑇𝑖𝑖 𝑖𝑖 , 𝑇𝑇𝑜𝑜𝑜𝑜𝑜𝑜 )
 SCR modelling as a continuous, ideal tank (CSTR, 0D-modelling)
 Arrhenius-approach for modelling reaction rates
 Introduction of an additional state finj in order to compensate on drift effects

17. Extended Kalman Filter - Example: Correction of NH3 Load in SCRF
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors17
 Significant advantage of Kalman-filter: Adaption is functional with parametrization of the model.
H(1)*10^4 -1.0
-0.5
0.0
0.5
1.0
Geschw.[km/h]
0
100
200
Temp.
[°C]
0
100
200
300
H(1,1) defines the direction of the NH3 load correction
Correction when NOx-slip occurs operating
in the opposite direction from NH3-slip.
NH3
NOx
0
NH3-slip
𝑐𝑐𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠,𝑜𝑜𝑜𝑜𝑜𝑜
= 𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁,𝑜𝑜𝑜𝑜𝑜𝑜 + 𝑐𝑐𝑁𝑁𝑁𝑁𝑁,𝑜𝑜𝑜𝑜𝑜𝑜
𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁𝑁
𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁𝑁
𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁𝑁
𝜂𝜂𝑆𝑆𝑆𝑆𝑆𝑆
𝑦𝑦 = 𝑐𝑐𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠,𝑜𝑜𝑜𝑜𝑜𝑜
𝑑𝑑𝑐𝑐𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠,𝑜𝑜𝑜𝑜𝑜𝑜
𝑑𝑑𝑐𝑐𝑁𝑁𝑁𝑁𝑁𝑁𝑁
NOx-slip
unobservable
Observable through
RF antenna!
Correction because
of NH3 slip
Correction because
of NOX slip

18. Without EKF
With EKF
With EKF and slip recognition
Results of Tolerance Analysis with IAV SCR Control
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors18
 When NH3 slip recognition activated, no more aberrations
 Variance of the other results smaller compared to EKF only
Dosing Control with EKF
gets difficulties, if
tolerances accumulates to
NH3 slip

19. SCR Control with Extended Kalman Filter - Prospects
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors19
Additional
Input
 Advantages for combination of closed-loop control with RF antenna input
Antenna
Calibration

20. Model Based Dosing Control
Overview
IAV/Continental 09/2019 Moser - RF Antenna for SCR, TWC, GPF and Machine Learning for Load Measurement - 6th International Conference Aftertreatment & Sensors20
 Experiences with model based approaches for different SCR dosing systems available (on PC and HD side)
 Modular SCR dosing control concepts different layouts (single / tandem SCR, single or dual doser, w/ or w/o ASCR)
available
 Closed loop dosing control or intelligent adaptation strategy recommended for robust DeNOx
(Model Based Dosing Control incl. EKF recommended for robust dosing control in future requirements)
2009 2013 2017 2018 2019
SCR Demonstrator
(ETB & 1st vehicle tests)
Customer A (EU)
SW development
Virtual Demonstrator
Different HD projects in HD-team
Selected References for Model Based SCR Dosing Control:
Customer B (EU)
Demonstrator
Customer C (EU)
Demonstrator
Customer D (EU)
Benchmark
MTZ
Journal
no. 02 / 2017
7th International
MinNOx
Conference
40.Internationales
Wiener Motoren-
symposium

21. Contact
Marco Moser
IAV GmbH
Carnotstrasse 1, 10587 BERLIN (GERMANY)
Phone +49 30 3997-89176
marco.moser@iav.de
www.iav.com
Dr. Markus Dietrich
Continental Automotive GmbH
Siemensstr. 12, 93055 Regensburg (Germany)
Phone +49 941 790-3313
markus.dietrich@continental-corporation.com
www.continental-corporation.com