ABSTRACT

The speed (min^-1) for electric motors are normally much higher than the speed of the wheels because high torque requires high weight. For a lightweight system and the required power, you need high-speed electric motors. 

Typically, transmissions with four gears are installed, and these without shifting. For cars with smaller motor power (P < 200 kW) two-speed-transmission are proposed. Using these two-speed transmissions significantly improves both the efficiency and the driving range of battery-powered cars. The lay-out of such transmission will be introduced. 

For instance, we will explain a planetary transmission that uses an electromechanical shifting system, which eliminates the need for hydraulic pumps or valves and minimizes torque interruption. The inertia of the motor will be used for the torque at output-shaft during the shifting process.  

Author(s): Bernd-Robert Höhn, Yingying Zhang

ISBN: 978-1-64353-146-5