NEWS
Perfect performer
Prodrive develops control technology designed to improve starting in extreme cold
MOTORSPORT and automotive
technology company Prodrive has
launched an electronic control unit
(ECU) designed to monitor and
manage hydrogen fuel cells for
vehicles.
Fuel cell systems developer
Intelligent Energy built the fuel cell
with Peugeot in the project, the
result of a call by the Technology
Strategy Board.
Intelligent Energy chose Prodrive
to develop the control system
as the company had a rapid prototyping
controller and could take the
finished product, dubbed PP150,
through to production.
Pete James, Prodrive technical
specialist, said: ‘The ECU has to
monitor all the vital statistics of the
fuel cell, including the temperature,
the power going out of the unit, the
voltage it is developing, and the
amount of oxygen that’s flowing in,
to protect the fuel cell from itself. It
controls valves and actuators to
regulate the flow of hydrogen and
oxygen going in and the byproduct,
water, coming out.’
Prodrive claims the 50kW fuel
cell system is a first for the UK —
most are smaller, with the higher
power models mostly coming from
the US. Although it could be used
for other applications, Prodrive’s
ECU was specifically designed for
the stringent requirements of the
automotive industry.
Prodrive gave Intelligent Energy
one of its rapid prototyping controllers
on which to develop the
control strategy algorithms, and the
outputs to monitor and control the
fuel cell. From this, Prodrive built
the DP200 development unit.
‘The DP200 “has the top off” so
they could change the insides of
the unit as they were developing
the various actuators and sensors,’
said James.
‘We were able to take that specification
and create the bespoke
ECU for them — the PP150.’
Making an ECU to support the
new technology posed some challenges
for Prodrive. ‘Some of the
sensors and output drives were
16
FutuRe
of automotive technology
Vital statistics: Prodrive’s PP150 electronic control unit, specifically designed for the automotive industry, monitors cells
very different to what we’re used to
on an automotive vehicle. Conversely,
the standard drives used to
control fuel cells are not applicable
to the automotive industry, so we
had to design it to get those circuits
to work in both environments.’
The unit had to work within a
wide temperature range. The
automotive industry requires components
to work from -40ºC to
+85ºC but, under the bonnet, the
maximum rises to +125ºC. The
functionality of fuel cells made the
lower range a particular challenge.
‘If your car is left out overnight in
Sweden it can easily get to -40ºC
and you expect to just turn the key
and set off,’ said James.
‘It’s a real problem for fuel cells,
as they inherently have to be wet
inside, making the start-up procedure
of a fuel cell difficult. So the
ECU itself needs to be up and running
at -40ºC so it can control
everything in the correct way on
start-up.’
The system is now undergoing
tests fitted in a taxi, and the next
stage would be a small fleet trial.
The next Technology Strategy
Board project for Prodrive, a DC-to-
DC power converter for hybrid and
all-electric vehicles, aims to take
the technology to the next stage.
‘The converter takes the energy
from whatever storage device you
have, whether batteries, fuel cell or
supercapacitors, and it transfers it
to the level required for the electric
motor,’ said James.
‘It basically balances the
sources out so you can use your
batteries or your fuel cell more in a
better optimised way. The unit
we’re designing is 50kW so it
matches the fuel cell nicely and
we’re trying to design something
smaller, lighter and lower cost than
currently available.’
James claimed that no equivalent
system exists for the
automotive industry yet, so it could
be key to the future of hybrid and
all-electric vehicles. It would make
them more practical by reducing
the size of the capacitors or batteries
for the same level of energy
storage.
‘One of the problems with fuel
cells in general is they’re a bit
lethargic — if you step on the accelerator,
they take a couple of
seconds to come online,’ said
James. ‘As soon as you take your
foot off, they still want to give you
power and they can get damaged if
you don’t use the power they’re
delivering.
‘If you can match the fuel cell
with some batteries or supercapacitors,
you’ve got another power
source to give you the transience.
But this only works if you can manage
the power between them
correctly, and that’s where a DCto-DC
converter comes in.’
Alongside the fuel cell system
now under test, James believes
that together the systems could
form a complete solution for
future fuel cell, electric and hybrid
vehicles.
Berenice Baker
the EnGIneeR 21 APRIL–4 MAY 2008
To view a Ceros magazine you need to have JavaScript enabled in your browser and have the flash player 8 or higher installed. To install the latest flash player, click the icon above, install the flash plugin and then click here to refresh this page.