SUPPLIER INTERVIEW: FUJITSU COMPONENTS EUROPE
“Our relays are
designed to cope
with harsh conditions”
Ben Schulte, business development manager automotive,
Fujitus Components Europe
www.electrichybridvehicletechnology.com // July 2019 // 147
safe to work with.” In addition, there is a range
of relays for the EV that will be expanded in
the future, and is currently able to handle 450V,
up to 150A and in the near future up to 400A.
“Our aim with the developments of these relays
is to ultimately reach 1,000V and 400A,”
reveals Schulte.
One of the challenges in designing the
relays, he goes on to explain, is the compact
spaces into which they need to be fi tted, which
Schulte says is more or less as confi ned as they
can be because “we are ultimately restricted by
the laws of physics from going any further in
minimization.”
Looking ahead and just how to achieve the
potential of 1,000V, he reveals that some of
rival companies are using inert gas inside the
relay to prevent a constant electric arc between
the contacts, “but we are not using gas because
we believe that using inert gas will not sustain
long-term eff ectiveness.”
Instead, he says several other options have
been implemented or are being explored. “We
are using multi-contact relays in series, and we
are also using a magnetic solution by the side
of the relay contacts, which will extinguish the
electric arc and can therefore also work in a
smaller contact gap or relay.”
The possibility of using plates between the
contacts is being investigated, but, as Schulte
explains, “this is something that will not reach
prototype stage for another two years or so.
Ultimately, to achieve 1,000V, we have to
minimize contact resistance and use smaller
relays. Low contact resistance means less
power loss in the relay, so we have to fi nd the
most eff ective way to achieve this. What’s
also important is the geometry of the contact,
the form, the pressure, and the material
used. Material choice will have an impact
on component lifetime because the relay’s
contacts need to be able to handle high
energy and contact pressure.”
Extended use
Schulte recognizes that there is an EV demand
for silent 12V relays and he is waiting to see just
how wide this requirement will become for
further relay use. “We expect to see the
demand increase,” he comments, “and this is
when things like double housing and special
springs will be important.” The components
will also need to become smaller, he says,
because OEMs want the entire package to be
smaller and smaller, something OEMs see
as a potential cost saver.
While relays are predominately used
onboard a vehicle – and here it’s important to
keep in mind more than just cars, with EV bus
and bike markets growing – but according to
Schulte there is scope for widening the use of
relays outside of a vehicle, for example in
charging systems. “Our relays are specially
designed to cope with harsh conditions, which
external equipment often has to deal with.
They can withstand vibrations and a wide
temperature range, from -40°C – +120°C -40°F
– 248°F, which is far superior to the standard
power relay that is often employed for such
tasks. There is, therefore, much growth
potential for the use of automotive relays in
contexts such as these.”
To ensure that the relays of the future can
fully handle the power and other expectations
of the industry, Schulte and his team’s
communication channels are open to
engineers who wish to share their
requirements for automotive relays in a bid to
try to establish wider industry standards,
which are currently lacking, and plans for
future developments.
2. The company is aiming
to expand its range of
relays to include 1,000V
and 400A
3. Fujitsu offers relays in
three groups: power,
signal and automotive
2
3
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