But why is a single gear enough for the drive motor?
With an electric drive system, the maximum torque is available immediately and remains constant over a wide range of speeds.
The use of a multi-speed gearbox to achieve the desired speed or the necessary torque along the speed curve is therefore not absolutely necessary.
That is why a 2-stage 1-speed gearbox is used in the fully-electric C-segment Volkswagen ID.3 passenger car.
When reversing the car, the direction of the electric drive system is simply reversed.
Small shifting unit: the 1-speed gearbox.
In addition to various other components, power electronics is responsible for this and for the power characteristics of the drive system.
In order to achieve the maximum power of 150 kW, the electric drive unit must rotate at high speeds.
In order to provide a high level of torque, a 10x transmission ratio is used.
To save space, the gearbox has a two-stage design with two smaller cogs instead of one big one.
As a result, the electric drive motor in the ID.3 provides the maximum torque of 310 Nm constantly over a wide range of speeds.
The maximum speed of 160 km/h is reached at a maximum of 16,000 rpm.
Because an electric drive system is very quiet, the level of noise in an e-vehicle is very important.
Even the tiniest sources of noise can suddenly be heard.
The parts for the 1-speed gearbox must therefore be manufactured with great precision to ensure that they do not cause any additional noise.
At the end of the production line, not only the power characteristics of the electric drive system are checked – the relevant noise values are too.
All drive systems for European and North American e-vehicles based on the MEB – including the 1-speed gearbox – are manufactured at the component plant in Kassel.
