New ID.3 Needs Only One Speed, Here is its Transmission
With electric vehicles revolutionising the way cars are powered, it makes sense that there are big changes throughout the driveline. Like this, the new one-speed gearbox used to proper the new ID.3 quickly and silently. And efficiently.
In a gas or diesel engine, torque starts out small, rises, peaks, and falls, usually all over a relatively small band of revolutions per minute. With an EV, peak torque is there from the jump and it stays flat over a far wider range of speeds. Because of that, VW says, a conventional multi-speed transmission isn’t needed. You don’t need to constantly vary the RPM with road speed to balance acceleration and efficiency.
So for the ID.3, a two-stage, one-speed gearbox was designed. It doesn’t even need reverse gearing, they just spin the motor the other direction. To make the car’s peak 201 hp, the electric motor spins at high speeds. To give the car lots of torque at the wheels, not just at the motor, a 10:1 ratio is used. The two-stage design means two small cogs do the multiplication instead of one massive one, saving space and weight. It lets the motor make loads of torque and hit a top speed of 160 km/h at the max motor speed of 16,000 rpm. There’s still a differential integrated, in order to route power to the tires and do the other fun things differentials do.
Volkswagen says that the lack of a noisy engine poses other gearbox challenges. The parts are made with “great precision” so that gear whine doesn’t show up to ruin the silence of the missing engine. VW’s end of the line QA checks now include not just the drive system’s function, but how much noise it’s making.
The new ID fixie, as we’re now calling the one-speeder, is built in Kassel, Germany, along with all drive systems for Euro and North American MEB-based electric vehicles.
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