ZF has introduced a new electric 2-speed drive solution for the passenger car segment. To increase the performance rating of the new electric axle drive system, ZF leveraged its expertise in systems to develop a new electric motor with a maximum power rating of 140 kW ( 188 bhp) paired with a two-stage shift element. Bert Hellwig, Head of System House at ZF's E-Mobility division,"For electric vehicles in everyday use, it is important to obtain as much range as possible from each battery charge. Every percent of improvement in energy conversion efficiency translates into two percent more range."
Vehicles with the new 2-speed drive consume less energy, which in turn extends range by up to five percent when compared to a one-speed unit. Shifts take place at 70 kmph. By connecting to the vehicle's CAN communication it is also possible - if the customer so wishes - to devise other shift strategies, possibly linked to digital map material and GPS. For example, the vehicle could identify from the GPS route programming how far it is to the next charging station, enabling it to respond predictively by switching into Eco-mode. More effective shifts would also be possible in accounting for topography on the interstate, and on inter-city journeys. The software in the drive can also be updated thanks to the network link to Cloud services via over-the-air updates.
The software in the drive can also be updated thanks to the network link to Cloud services via over-the-air updates.
For vehicle manufacturers, the new 2-speed drive offers two options for using improved energy conversion efficiency. The Original Equipment Manufacturer (OEM) could either go for an extended range while retaining the same size of accumulator, or utilize a smaller accumulator.
The design of this unit optimises installation space, the 2-speed system is suitable for compact passenger cars where interior space is at a premium.
The 2-speed concept offers benefits for OEMs who are pursuing performance. ZF's modular approach combines the 2-speed gearbox with even more powerful electric motors rated for up to 250 kW.