Lucid Motors calls its motor design miniaturized, and it’s lengthy boasted that the sunshine and “impossibly compact” motor in its Air electrical sedan is lean sufficient to suit into an airplane carry-on.
Lean and small is just one facet, nonetheless. Lucid’s motors weigh simply 67 kilos every and are able to producing 670 hp—sure, that’s 10 hp per pound.
2022 Lucid Air
Additional, Lucid’s silicon carbide inverter, discount gearset, and differential, packaged collectively, weigh about 163 kilos.
It is rather, very power-dense. And in a tech discuss launched by the corporate on Tuesday, Lucid CEO and CTO Peter Rawlinson and Powertrain VP Emad Dlala ran via the priorities the motors have been designed round, and the way energy and effectivity, via low resistance and thermal administration, have been a part of the plan from the beginning—together with ease of producing.
You’ll need to watch the complete presentation—greater than an hour—for the physics lesson inside, and also you’re certain to be taught lots not nearly this unit however motors normally. However these 4 slides, evaluating Lucid’s motor to motors from Tesla and Porsche, get to the gist of it.
Lucid weight of stator and rotor in contrast
Lucid motor weight in contrast
Lucid energy density in contrast
Lucid energy and motor weight in contrast
Rawlinson notes that the undertaking included going again to the physics and looking out on the complete powertrain as a single holistic inertial system.
The 2 spend a lot time discussing the design of the stator—the static outer portion of the motor that, with the present formed by the inverter, creates the magnetic area that rotates the rotor within the center.
For example, the stator for Lucid’s six-pole permanent-magnet synchronous motor doesn’t use copper-wire windings like many such motors, and it doesn’t use hairpins both. As an alternative, for decrease energy losses plus ease of meeting, Lucid seems to a continuous-winding meeting that wraps into the stator with a restricted variety of welds. It’s made with a CNC-controlled machine and a course of that resembles weaving. Then a CNC-controlled mandrel helps align and insert the woven mesh.
Carbon wrap on Tesla Mannequin S Plaid motor
The pair even poke a little bit enjoyable on the workaround that Tesla resorted to in its motors for the Plaid—a carbon-fiber shell that Rawlinson notes is similar type of know-how utilized in hydrogen storage for gasoline cells, to carry great strain in. To scale that to excessive quantity goes to be very costly, Dlala speculates.
Lucid additionally cools its motor in another way than Tesla, Porsche, or every other designs we’re conscious of. Lucid’s technique extracts no matter warmth it will probably super-close to the slots reasonably ready till the warmth reaches outward. A center channel within the stator features as a manifold, working ATF (automated transmission fluid) via slim channels, serving to extract warmth via that mesh.
The busbars connecting the motor to the inverter are additionally the shortest potential, to cut back resistance (and thus warmth). It’s a bonus of the motor because it was designed in a single unit with the inverter.
Lucid’s Rawlinson and Dlala presenting drive unit
Backside line: Lucid emphasizes that its drive models are mild, compact, environment friendly, power-dense, and could be scaled up.
Though Lucid doesn’t truly lay out an effectivity evaluation of the motor unit versus the unit from the Taycan and Mannequin S Plaid, it implies based mostly on the entire presentation that its motors additionally make an enormous contribution to effectivity.
To that time, Rawlinson ventures that the motor itself weighs so little—simply 11% of the general battery-pack mass—that if they will obtain that acquire in effectivity from the unit’s design it’s primarily a “zero mass drive unit.”