powertrain engineering
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compliance and avoid penalties.
The hybrid powertrain is, therefore,
being considered as one way
to reduce CO2, GHGs and other
pollutants, while offering performance
and cost characteristics
that enable operators the flexibility
to operate as they did prior to
hybridization.
Hybrid powertrains – conventional
internal combustion engines
augmented with electrified components
– vary in configuration,
resulting in different degrees of
hybridization. The 48 V mild hybrid
system, for example, features
a conventional engine with electrical
auxiliary systems, such as water
and steering pumps.
Different configurations suit different
mission profiles and vehicle
specifications, and each has its own
pros and cons. Mild hybrid configurations,
for example, do not offer
full electric mobility, and so are unsuitable
for zero-emission zones.
However, mild hybrid variants require
the least transformation of the
powertrain, which results in lower
vehicle costs than full hybrid
options. They also have a lower
payload penalty, as the additional
weight of components such as the
battery is lower.
ENERGY
MANAGEMENT
To make any powertrain as efficient
as possible, energy must not
be wasted. To optimize the system
even further, it must recuperate energy
during driving. However not
all driving cycles are suited to support
this.
Long haulage trucks, for example,
which drive for long distances at
a consistent speed, offer fewer opportunities
for energy recuperation.
However, local delivery vehicles,
which operate in urban traffic and
typically undergo frequent deceleration
and braking, have a large energy
recuperation potential.
This energy can then be used in
the next acceleration event to reduce
net energy consumption even
more, reduce the use of the combustion
engine and cut fuel consumption
and emissions.
If such a vehicle had a large enough
battery, it could even operate fully
electrically to enter zero-emission
urban zones.
THE COST OBSTACLE
All innovative technology comes at
a price, and the commercial vehicle
market is driven primarily by
cost. So, it’s important to guarantee
an acceptable TCO for the end
user, while allowing OEMs to meet
global CO2 fleet targets.
It is these targets that AVL is helping
OEMs to achieve. With 70 years
powertrain development experience
we understand our customers,
and have solutions to make their
goals a reality. This includes an array
of tools and services that can be
tailored to their needs. We can offer
support in single tasks, or take responsibility
for entire development
projects. In the case of third-party
components, we can also support
supplier screening and selection.
We can guide with early concept
investigations using our simulation
tools, and based on the results of
these studies continue with system
design for projects such as Dedicated
Hybrid Transmission (DHT)
configurations.
Beyond our efficient simulation solutions,
we can also quickly build
prototypes and demonstrator vehicles.
With our long history of
engine, aftertreatment and vehicle
calibration, we have created a full
toolchain to ensure short development
times, reduce calibration and
test effort, and marry performance
with low fuel consumption and
emissions.