Back in July, YASA (formerly Yokeless And Segmented Armature), a British electric motor startup with a revolutionary ‘axial-flux’ motor, was acquired by Mercedes-Benz. As little else was announced, the acquisition did not attract a lot of press attention. YASA will be a entity that is worth keeping an eye on.
Founded in 2009 after being spun out of Oxford University, YASA will now develop ultra-high-performance electric motors for Mercedes-Benz’s AMG.EA electric-only platform. The company will remain in the UK, as an entirely owned subsidiary. It serves both Mercedes-Benz customers and Ferrari. It will keep its brand, staff, facilities and Oxford location.
YASA’s axial flux electric motors attracted EV industry attention because they were efficient, low in weight, and high power density.
The ‘radial electric motor’ design, however, is much more popular in the current EV market. Tesla is dependent on the radial motor design, which is a 40-year old technology that has very limited innovation potential.
YASA’s axial flow design with very thin segments means that they can be combined to make powerful single-drive units. They are one-third as heavy as other electric motors and have 3x more power density than Tesla.
Tim Woolmer, YASA’s Founder and CTO, invented this very new approach to electric motor design. To find out more, I met up with him.
TCHow far have we come?
TW: Our company was founded just 12 years ago. We have one goal: to accelerate the development of electric cars. Let’s make them happen quicker. Now, 10 years have passed and we are in the midst of a 20 year revolution. Every new vehicle that is sold within 10 years will be an electric car. Engineers find nothing more thrilling than experiencing a time of rapid innovation. We get to invent fast which is what makes this partnership so interesting.
TCComment: Was there anything different in the engine that you created?
TWAt the start of my PhD, we started off with a blank piece of paper. The idea was to ask, “What could we create for electric cars in 10 or fifteen years?” A lighter, smaller, and more mass-producible vehicle. Axial flux motors weren’t very popular in the 2000s. However, by using axial flux technology with a few tweaks and new materials I came up with this design, which we now call YASA: Yokeless and Segmented Armature. This takes an already light topology of axial flux, and makes it lighter by making it half the weight. Because the rotors rotate at a larger diameter, there is a benefit. The torque formula is simply force multiplied by diameter. This means that you will get more torque for the same amount of force. Double your diameter and you will get twice the torque with the same materials. This is the advantage of axial flux.
TC: This is the deal you made with Mercedes. Now what?
TWBasically, we are a 100% owned subsidiary. Mercedes is our industrialization engine. The key point is that technologies start in luxury sectors like Ferraris. They then move into the mainstream sector before reaching higher volumes. This is a sector where Mercedes has a world-class industrialization. That’s why the partnership was formed.
TC: Other things you can do here
TWOur engine will be very powerful, lightweight, and low in power. This allows us to explore the combination of high industrialization levels with sport performance. This puts us in an extremely unique place for many things.
Woolmer, despite being coy about what his future plans are, is definitely one to keep an eye on in the electric vehicle and motor industry. This video was released by YASA after the acquisition.
Publited Fri, 3 Sep 2021 at 14:43.51 +0000