Koenigsegg is continuing its in-house technology development and advanced electromobility component offerings. It started with David, the recently introduced 6-phase inverter, followed by the company’s newest innovation, the Quark electric motor that utilizes a novel torque/power-rich balance between radial (power-dense) and axial (torque-dense) flux topology dubbed Raxial Flux.
Koenigsegg has integrated two Quark E-motors with one David inverter, plus planetary gear sets, in order to create the class-leading Terrier, a torque-vectoring EV-drive unit.
Quark Electric Motor. A key driver for the development of the Quark E-motor was to continue the company’s work with the Koenigsegg Gemera—a limited production four-seat plug-in hybrid grand tourer—while offering the wider market the opportunity to tap into a torque-rich, ultra-compact e-motor for wide-ranging applications, such as EV powertrains, Aerospace, VTOL, Marine and more.
Koenigsegg’s Quark motor with a 330 ml beverage can for scale.
The Quark motor weighs around 28.5 kg, with a volume of 8l. Nominal system voltage is 850V, with peak power of 250 kW, peak motor torque of 600 N·m, and max motor RPM of 9000. Peak power density is 8.3 kW/kg.
The mixing of radial and axial flux layout enables the best torque to power-to-weight ratio in the industry, the company said. Spearheading this development is Electric Motor Design Lead Dragos-Mihai Postariu who comments:
The Quark is designed to bolster the low-speed range of the Gemera, where you need it, for brutal acceleration. The ICE then focuses on the high-speed range. What this means in terms of performance for the Gemera is a big power surge followed by a continuous record-speed push to 400 km/h without any torque or power losses.
E-Motor Development Lead András Székely explains how Koenigsegg combated weight penalties:
We constructed the shaft within the Quark out of 300M steel used in motorsports and aerospace. Direct cooling was chosen for its higher cooling efficiency and compact design. Even the rotor uses the renown Koenigsegg Aircore hollow carbon fiber technology (presently used in Koenigsegg’s rims, steering wheel, seats, etc). We not only overcame the challenge of the Gemera’s powertrain requirements but also exceeded goals of making it lighter and smaller than any electric motors in this class. The Quark presents new benchmarks in compact and torque-rich engineering with the first production version weighing just 30 kg, producing up to 600 N·m of torque and 250 kW of power. Without the extra driveline functions for the Gemera, the Quark can drop below 28.5 kg in weight.
Power and torque diagram for the Quark E-motor
The Quark is unique in its high efficiency in combination with its class-leading torque-to-power-to-rpm-to-weight matrix. This means, when using the Quark in applications such as marine, aircraft or VTOL, there is no need for a step-down transmission, instead direct drive can be achieved, as the RPM of the motor is right from the get-go. Small high-revving motors can have higher peak power to weight ratio, but they need transmissions in most applications in order to get to the desired output rpm and torque, causing energy loss and adding weight and complexity to do the same job. So any benefit in size is lost. In other cases, like the Terrier application, the transmissions can be reduced in size and complexity compared to higher-revving, less torque dense motors, which is also a big win. I guess we’re trying to reach the edge of optimal in-betweeness.
David inverter. Koenigsegg unveiled the David SiC six-phase inverter in early December 2021. The David inverter is fully developed in-house for the Gemera and other future needs.
Weighing only 15 kg with a volume of 10 liters, the ultra-compact inverter kicks out 1300 ARMS AC at 850 V (DC) over 6 phases, with up to 750kW of power. In double configuration (30 kg of weight with a volume of 20 liters) as mounted in the Gemera, there are 12 phases (6 per motor) with an output of 1.5MW—a new benchmark.
As the inverter is smaller, lighter and more powerful than what we could find out there, we named it David, like in the story of David and Goliath.
David runs on proprietary Koenigsegg flexible algorithms and software that is continuously upgraded over the Koenigsegg cloud via OTA. David is capable of either running two motors independently or one motor up to 750kW. Fully sealed housing and quick connectors allow safe connection without opening the casing or using special tooling.
David was developed under the ISO 26262 regulatory framework and international high voltage safety standards. David is optimized for harsh automotive environments and designed to emit low electromagnetic emissions.
David also comes in versions directly busbar-integrated with Koenigsegg E-motors, as an alternative to stand-alone integration via cable. Doing so will shrink David down to around 9 liters in volume.
The Terrier EV Drive Unit. The launch of the Quark E-motor, in parallel with the recently unveiled David inverter, enabled Koenigsegg to create the Terrier. A two-Quark-one-David configuration presented an opportunity to create the most power/torque dense, torque-vectoring drive unit in the EV industry.
In traditional Koenigsegg fashion, the drive unit has been named—Terrier, since both the dog breed and the drive unit are characterized by their small, energetic and fearless demeanor.
Terrier EV Drive Unit in between Quark and David
The Terrier surpasses today’s drive units, needing only one inverter (instead of two), as David’s 6-phase lends 3 phases to each Quark, thereby significantly reducing weight, size and components. Furthermore, given the Quark’s flat packaging, David can neatly slot between two Quarks to create a square super-dense package. Finally, as the Quarks give massive power and torque at reasonable RPMs, only small low-ratio highly efficient planetary gear sets are needed at each output.
The Terrier unit is 340 mm x 475 mm x 425 mm (H x W x L). With driveshaft tulips, the width increases to 620 mm. The unit weights 85 kg with a volume of 40 l. Nominal system voltage is 850V, peak power is 2 x 250 kW, peak motor torque is 2 x 550 N·m, and peak power density is 6 kW/kg.
The compact and unique packaging allows the Terrier to be elasto-bolted to the monocoque or chassis directly, thus allowing for design, engineering and luxury accommodations previously not possible. This trait also potentially cuts away the complexity of added subframes or weight.
More information on Terrier and Koenigsegg’s fast-growing HV architecture to come.