Automotive Engineering - March 2024 - 23

ELECTRIC MOTOR ADVANCES FEATURE
Magna's e-motor can
be rotated 90 degrees
around the drive axis
with no modifications.
Both horizontal and
vertical installations
keep the coolant pump
at the bottom, where
it needs to be.
MAGNA
puts multiple
innovations in new, more
efficient 800v e-motor
Better cooling and more efficient chip placement are among the techniques used
to hit a new company high for efficiency: 93%
by Chris Clonts
A
t the Consumer Electronics Show in Las Vegas, Magna
International showed off a new 800-volt e-drive motor that
it said sets new standards in efficiency, power-to-weight
ratio and torque density.
Joerg Grotendorst, senior vice president of corporate R&D, included
the announcement in an overview of Magna's recent focus on
e-motors, improving ADAS and impaired-driver detection.
" Our response to the increasing cost-cutting demands of the OEMs
is to work with (a philosophy) we call Magna Integrated Systems, " he
said, explaining that it is more efficient to produce a system for an
OEM rather than just a component here and there. Which the company
is still willing to do, of course.
The 258-kW peak-power unit can generate peak axle torque of
5,000 nM (3,688 ft-lb) while hitting a max of 20,000 rpm. It does this
in a package weighing only 75 kg (165 lbs). It reaches 93% efficiency,
an improvement over other Magna offerings' high of 91%. It's equivalent
in capabilities to a five-liter hemi, one engineer said.
The enhancements driving that efficiency include the ability to
route cooling fluid to the components that need it the most at any
given time and a new way of embedding the controller chips.
Mike Dowsett, Magna's chief engineer for powertrain electrification,
further detailed the motor's innovations, not the least of which
is its ability to be used horizontally, typically when it's at the rear of a
AUTOMOTIVE ENGINEERING
vehicle, or vertically at the front. The key is that when
the motor is rotated 90 degrees, the pump for the
coolant still is located at the bottom, where it must be
to function properly.
" This is active cooling fluid control, " he said. " It increases
efficiency by moving oil to different locations
based on the power demands. For low-speed and
high-torque situations, more cooling is directed to the
magnets. For high-speed and low-torque, it is directed
to the jacket and the windings, which are traditional
non-braided windings. "
Asked about whether Magna was considering
printed circuit board (PCB) stators instead of windings,
something being promoted by companies such
as Schaeffler and Infinitum, Dowsett said the company
didn't believe that today's power demands
could be met that way.
Dowsett said Magna has accounted for bearing current,
a damaging phenomenon in which electrical current
from the magnets finds its way to the bearings
and exceeds the breakdown voltage of the lubricant.
This causes pitting and fluting of the bearing races and
can prematurely ruin a motor.
March 2024 23
SAE/CHRIS CLONTS
Automotive Engineering - March 2024

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