Dynamic counterpart of the Volvo EX90?
Volvo and Polestar are launching a large electric car based on the same technology. The Volvo EX90 will be a large seven-seater, while the sportier Polestar 3 can accommodate five people. We still have to wait a while for both, but AutoWeek was the first and only Dutch media to take to the test track with a Polestar 3 prototype. Is this worth the wait?
What kind of car is the Polestar 3?
The Polestar 3 is a large electric five-seater. We would label it as a crossover, but the Swedish/Chinese car manufacturer considers it an SUV. In June 2022, Polestar pulled back the curtain; The car is not expected in the showroom until next spring (2024). To get an idea of what kind of car the new Polestar is, we drive it on the test track in Hällered, Sweden, where Volvo also develops its cars. The lines with sister brand Volvo are in any case so short that the Polestar 3 shares its scalable platform architecture with the Volvo EX90, which is also yet to be introduced. The latter, with its seven seats, is the more practical variant of the two, while the Polestar with its sloping roofline represents the sporty branch of the family. Both have a serious wheelbase of 2.99 meters, but due to the lack of a third row of seats, you have plenty of space in the back of the Polestar.
It looks cool, can it also go off-road?
We start our introduction on an off-road course where the four-wheel drive can hold its own. While the air suspension (with two chambers for different characters) ensures maximum ground clearance, the BorgWarner differential is busy proactively supplying the right torque to each rear wheel. There is no such system at the front, where more or less the same effect is achieved by individual braking interventions (but reactive). The 3 effortlessly climbs up a 45% slope with the left wheels in the grass and the right wheels on the frozen asphalt. Before we know it we are on top of the hill, on Pirelli P Zeros, not exactly an off-road tire. The car also does the diagonal crossing of an apparently unbridgeable ditch (where the left rear wheel and the right front wheel simultaneously dangle in the air halfway through) without complaining. The electronics are working continuously to get the car where we want it. Will you ever use these off-road capabilities? No idea, but it’s at least nice to know it’s possible.
Torque Vectoring, how does it work?
Just like tracked vehicles, you can also help cars steer by varying the driving forces left and right, we then talk about torque vectoring. This is relatively easy to achieve with the 2019 Polestar 1 because the rear wheels each have their own electric motor. In the four-wheel drive Polestar 3, the rear wheels share one electric motor, as do the front wheels. This requires a different solution. Two even. A standard differential sends the same amount of torque to the right as to the left. The electronics can create a torque vectoring effect by braking one wheel in a controlled manner, simply with the disc brake. Both wheels receive 50 percent of the torque, but one wheel has to give up part of the brake. This way the other wheel has more torque to put on the road. The Polestar 3 uses this method on the front axle.
How does torque vectoring work on the rear axle?
The rear axle of the Long Range Dual Motor has a BorgWarner dual-clutch differential. These transmit the torque from the engine to the left and right wheels. With both clutches closed, both wheels receive the same amount of torque. But by closing one clutch and opening the other more or less, the torque going to the wheels varies. In Range mode (eco mode), the Polestar 3 is a front-wheel drive. The couplings of the rear differential then both open, the rear electric motor does not rotate idle and this saves up to eight percent energy in the drivetrain.
How fast is the Polestar 3?
While Volvo currently limits all its models to a top speed of 180 km/h, Polestar simply goes further. On the large bowl track, the prototype of the 3 effortlessly reaches its top speed of 210 km/h, and according to the speedometer it even exceeds it: 215 is stated in the digital instruments. With its 517 hp, the car does not flinch and makes its rounds extremely stable; it proves to be a comfortable traveling machine.
What do you notice in the practice of torque vectoring?
When we track the 3 on a winding handling circuit a little later, the effect of torque vectoring is once again underlined. The large Polestar can also be steered through the bends with extreme stability at pace. The steering is a little bit distant, but that shouldn’t spoil the fun. The car reacts extremely neutrally, understeer and oversteer seem to the 3 unknown terms, as if it is running on rails. Apparently resigned, the car lets it happen when we try to push its limits. However, that is outward appearance. Behind the scenes, the systems are working unnoticed for us to ensure everything runs smoothly: with an occasional quick glance at the iPad of the engineer driving along, we see a neat display in real time of how the driving forces are continuously distributed between right and left. If there is anything to criticize about the 3, it is perhaps the lack of handles on the ceiling. We missed this a number of times when we wanted to fixate on banked slopes and in fast corners.
Has the Polestar 3 always been this advanced?
Don’t be surprised if tamer versions of the Polestar 3 appear later with a normal rear differential and coil springs. According to the engineer in the passenger seat, these are excellent alternatives to reduce costs. And although the engineer does not want to say whether there will also be two-wheel drive, remember that the Volvo EX90 is not only offered as a four-wheel drive but also as a rear-wheel drive (just like the Polestar 2, by the way). But we haven’t gotten that far yet, when the frost comes out of the ground in the Far North, the big four-wheel drive vehicles with 489 and 517 hp will first come our way.
– Thanks for information from Autoweek.nl