Powertrain & Vehicle
Research Centre
Low Carbon Powertrain Development
S Akehurst, EPSRC Advanced Research Fellow
Lean Powertrain
The vehicle powertrain is the system that converts
Realism
Vehicle
Vehicle
TestTest
raw fuel into tractive motion at the wheels. It is a
Lean Powertrain Development
Lean
complex combination of interacting sub-systems Powertrain
ct
du
under computer control with multiple actuators and Development
o
aims to
Pr
sensors. The lean powertrain development project maximise the
Mistakes
accuracy and
al
identified late
aims to increase the validity and realism of the early realism of
n
i
in the
F
Rolling Road
early
s
development
stages of the vehicle development process, by
rd
powertrain
a
process cause
w
increasing the utilisation and accuracy of simulation development
costly
To
tasks to
Advanced Engine Test
recycling of
tools and applying novel experimental techniques reduce costs
the powertrain
and time to
Basic Engine Test
development
and procedures to evaluate prototype hardware
market
process
before it is readily available. This should deliver
Powertrain Simulation
Cost & Complexity
future, more efficient vehicles to market in a shorter
timeframe and at reduced development costs.
Engine Modelling
Engine modelling in the powertrain development
process is often separate from the experimental
Applying Design of Experiments to Develop Models
program. Techniques developed in the lean
Experimental
Experiments
Build Models
powertrain project utilise design of experiments
“One Click” Simulink
Design
Model Block
(DoE) techniques to maximise the use of simulation
and experimental data, which can be combined to
develop response surface models for important
Cycle Simulation
engine responses. These responses, to a range of
Classical or
Polynomial Models
Space Filling
actuator inputs, can be rapidly optimised using
Neural Networks
Designs
mathematical algorithms to identify desired operating
Radial Basis Functions
Engine Test
conditions and requirements for future hardware.
A further benefit is that the response surface models
may be utilised in real time engine modelling tasks
for controller development and in Complete
Historical Data
Powertrain Emulation as described below
Advanced Boosting Strategies
Complete Powertrain Emulation
Increasing air flow through an
engine is the primary means of
increasing power and fuel economy.
Techniques developed in the lean
powertrain project enable advanced
boosting systems to be emulated
before the prototype hardware is
available. This allows early proof of
Exhaust back
benefit and reverse engineering of
pressure valve to the new technology to meet desired
emulate turbine
performance requirements
Forced induction simulator
Boost Temp
to supply controlled air
To
Co
m
flow
to engine under test
pr
hardware
e
Mass Air Flow
From Engine
Manifold Pressure
ss
or
To
r
Complete powertrain emulation allows the entire vehicle powertrain to
be conceived early in the product development cycle. Real powertrain
components (in this case the transmission) are integrated with virtual
models of the engine and the vehicle. This enables early performance
assessments to be made at minimal cost. At this early stage integrated
control development and optimisation between the engine and
transmission can be undertaken to support tasks later on in the
development process.
Integrated Calibration and Optimisation of
Engine & Transmission Controller
Calibration tool
Advanced Transmission Facility Utilised
for Complete Powertrain Emulation
Virtual Engine &
Driver Models in
Real Time Software
qu
e
Inlet Pressure
Shaft Speed
VGT Position (ECU)
Pressure Ratio
Pulsating exhaust
pressure used
T
ne
rbi
Tu
u
orq
Real
Transmission &
Controller
Shaft Model
e
ω shaft = ∫
Tq turb − Tq comp
J shaft
Virtual Vehicle Model
in Real Time in
Software
Real Engine
Controller
Exhaust Temp
Exhaust Mass Flow
Viewing Trade-Offs and
Finding Optima
dt
Engine set
point to input
dynamometer
Input
Dynamometer
Emulates Engine
Output
Dynamometer
Emulates Vehicle
Dynamometer Control
Virtual software models of
boosting hardware send set point
commands to emulation hardware
Control & Data
Acquisition System
(Includes Safety)
Funded Under EPSRC Project Codes EP/C540883/1 & EP/C540891/1
Vehicle set point to
output dynamometer