Page 18 - EE Times Europe September 2021

18 EE|Times EUROPE

Pushing the Limits of Weight and Power Delivery in EV Hypercars

Kerr told me that the biggest challenge in the electronics design was
the complexity of the control logic to enable optimal control of each
axle. He added that the Evija had a full cloud-connected computing
solution behind it. The main aim for this is to be able to monitor cars,
which might be anywhere in the world, and to be able to reliably pre-
dict when a customer might need car servicing so that relevant support
can be provided.

WEIGHT REDUCTION: THE HOLY GRAIL
Common themes among the manufacturers at Goodwood were mini-
mizing system weight to improve power delivery efficiency, intelligent
airflow management to reduce drag and improve performance, and
effective delivery of power to the axle for precision control by the
driver.
McLaren, which showcased its new Artura, said minimizing weight
was key to the design of the all-new electrified powertrain, engineered
to offer the advantages of internal combustion and electric power in
one package and establish new benchmarks for combined performance
The McLaren Artura e-motor weighs 15.4 kg, only a little heavier and efficiency in the supercar class.
than a conventional iron rotor component. The axial flux design of its e-motor is one of Artura’s benchmarks.
(Source: McLaren Automotive) The e-motor is similar in size to a McLaren brake disc, and at just
15.4 kg, it is only a little heavier than a conventional iron rotor com-
The motors and inverters are supplied by Integral Powertrain Ltd. ponent, yet it can generate up to 95 PS and 225 N-m as well as enable
Four compact, extremely light, and highly efficient single-speed, helical journeys of up to 30 km in near-silent pure-EV mode.
gear ground planetary gearboxes transfer power to each driveshaft. Providing the electric-only capability is a 7.4-kWh five-module
Each gearbox comes packaged with the e-motor and inverter as a single lithium-ion energy-dense battery pack. Fully integrated into Artura’s
cylindrical electrical drive unit. With a target power of 500 PS McLaren lightweight architecture (MCLA) chassis, the battery pack
(approximately 493 HP) per e-motor, this is the most efficient and is positioned low in the car behind the driver, incorporated into the
elegant engineering solution for deploying so much power with floor, and protected on three sides by the main carbon fiber structure
precision. and from behind by the engine. This positioning helps to optimize
Torque vectoring, enabled by the four e-motors, provides good both the center of gravity and the polar moment of inertia, benefiting
dynamic response and agility on the road. This fully automatic, self- dynamic agility.
adjusting system can instantly distribute power to any combination of The hybrid battery sits on a cooling manifold, which is shared with
two, three, or four wheels within a fraction of a second. In track mode, the new electric heating, ventilation, and air conditioning system also
the ability to add more power to individual wheels enables the radius of used to control air temperature in the cabin. Incorporating tech-
corners to be tightened, potentially reducing lap times. nology first developed for the McLaren Speedtail, the batteries are

The McLaren Artura: Minimizing weight was key to the design of the all-new electrified powertrain, engineered to offer the advantages
of internal combustion and electric power in one package and establish new benchmarks for combined performance and efficiency in the
supercar class. (Source: Nitin Dahad)

SEPTEMBER 2021 | www.eetimes.eu