GKN Driveline has expanded its global electric axle (eAxle) drive partnership with the BMW Group, supplying eAxle technology for a plug-in hybrid version of the BMW X1 for the Chinese market. The system is part of the same family of eAxles used in the plug-in hybrid BMW 2 Series Active Tourer 225xe.
Early adopters of GKN’s electric axle drive used the technology to create plug-in hybrid sports cars (such as the BMW i8) with electric all-wheel drive that enhanced performance and efficiency. Automakers are now equipping a new generation of compact vehicles with GKN electric drive technology.
Peter Moelgg, Chief Executive of GKN Driveline’s AW&E Drive business, added: “Automakers’ evolving powertrain strategies require suppliers with a focus on mass-production of key technologies – and system integration capability. GKN’s hardware and software expertise is supporting the development of future platforms – these will need driveline suppliers to interface effectively with the rest of the vehicle’s electronic architecture.”
The system will be supplied from GKN’s facility in Bruneck, Italy, but application and development work for the technology was conducted by GKN’s operations in Shanghai, China.
For compact car applications, GKN’s single-speed design has a transmission ratio of 12.5:1, reducing the electric motor speed in two stages. The system generates up to 2,000Nm and 70kW of additional torque and power – enough for a vehicle’s pure electric mode to achieve speeds of up to 125km/h and for an all-wheel drive (AWD) mode that accelerates faster than conventional mechanical AWD systems.
The compact and lightweight electric axle weighs 20.2kg and is 457mm long, 229mm wide and 259mm high. When hybrid operation is not required, an electromechanically actuated dog clutch disconnects the e-machine from the driveline, minimizing losses at higher vehicle speeds. GKN has also optimized gear and bearing arrangements for optimum efficiency, NVH (noise, vibration and harshness) and durability.