British-based manufacturer GKN Driveline is unveiling an all-new electric axle concept at the Frankfurt International Motor Show (IAA) which opens today.
The axle, called eTwinsterX, features an integrated coaxial format meaning that the electric drive (eDrive) unit is significantly smaller than other systems with equivalent power outputs.
“eTwinsterX will deliver unrivalled capabilities for the next generation of electric vehicles," said Peter Moelgg, CEO of GKN Driveline’s eDrive business.
"It takes multiple award-winning elements from our GKN driveline portfolio and applies the principles in a single state-of-the-art electrified system."
The system can be used either for the primary drive in fully electric vehicles, or for the secondary drive on plug-in hybrid vehicles, creating a ‘split-axle’ driveline.
It employs an all-new two-speed transmission, which enables a better balance of acceleration and top speed than conventional single-speed electric drive units.
Moelgg said multi-speed transmissions enable electric vehicles to deliver better launch performance, using the lower gear, and more efficient high-speed driving using the higher gear. This strategy keeps the motor operating close to its efficiency ‘sweet spot’, meaning that it can optimise driving range.
Torque vectoring allows for intelligent control of vehicle dynamics by managing the distribution of torque to individual wheels. For example, by enabling over-speeding of the outside wheel in a corner, torque vectoring can induce a yaw-moment, helping to steer the vehicle more safely towards a tighter cornering radius.
It can also produce a negative torque effect to slow the vehicle. When a dynamic imbalance is detected across an axle, the system sends more power to the wheel with the higher traction. And when slowing down, the system can also stabilise the vehicle and recover kinetic energy at the same time.
The company says the system will appear in demonstrator vehicles from late 2017 and will be put through live trials in early 2018.
[GKN's new electric driveline. Image: GKN]