E-Mobility Hidden Champion
On their own, a big battery and a few electric motors won’t trigger an automotive driveline revolution. Electric cars are going nowhere without sophisticated power electronics.
Efficiency and precision are everything in power electronics – the technology that controls and regulates the type, voltage and level of just about every electrical current in the vehicle. Power must reach the components that need it efficiently and in exactly the right proportions – as well as flowing back and recharging the battery in an optimized recovery process. So it is hardly surprising that power electronics should be the most important component – the brains and heart, as it were – of any driveline that produces zero local emissions. To ensure enough power reaches the electric motor(s) in current ZF systems, the power electronics must be capable of handling up to 150 kilowatts – equivalent to the power input of 150 vacuum cleaners or around 30 domestic ovens – in a footprint of just 305 cubic inches. The following list outlines the various power electronics functions in more detail. Power electronics is an important part of the new E-Mobility division’s portfolio (see overleaf for more details of the division’s other products).
- Convert the direct current (DC) supplied by high-voltage traction batteries into high-voltage alternating current (AC) for at least one electric drive motor, and into low-voltage direct current for the vehicle’s onboard electrical systems (headlamps, heating, aircon, multimedia and so forth)
- Convert the high-voltage alternating current produced by the electric motor in generator mode so it can recharge the battery (regenerative braking)
- Regulate torque
- Ensure smooth transitions between driving modes (e.g. switching from Comfort to Eco mode)
- Use battery capacity efficiently
- Monitor the driveline’s power demands (e.g. coordinating the actuation of electric pumps with the main drive unit)