Last month, GKN Automotive unveiled the world’s first battery electric vehicle (BEV) with a two-speed transmission and torque vectoring.
Based on a standard Jeep Renegade, the GTD19 demonstrator vehicle is currently undergoing extensive testing at GKN’s annual winter testing programme in Arjeplog, Sweden, to show how automotive manufacturers “can use drivetrain innovations to achieve industry-leading standards of efficiency, safety and driving dynamics in BEV models”.
The GTD19 is equipped with an “optimised two-speed ‘seamless shift’ eTransmission and smart shifting strategy”, which has the potential to extend vehicle range as well as provide greater torque, acceleration and a higher top speed.
Efficiency is further enhanced by the GTD19’s eAxle’s coaxial format, while high levels of stability and dynamic performance are possible thanks to the torque-vectoring capability of GKN’s eTwinster system.
Hannes Prenn, COO of GKN ePowertrain (www.gkn.com
), said: “This new technology demonstrator showcases how we are evolving and improving integrated eDrive technologies to help OEMs further improve efficiency, safety and driving dynamics.
"Within the last year, we have seen a 40% increase in the value of our eDrive order book, rising from £2 billion at the end of 2017 to confirmed business now worth £3 billion.
"Our dedicated focus on the production and development of electrified drivelines will enable us to support the rapid
acceleration in demand for BEVs equipped with all-wheel drive systems in the coming years.”
The GTD19 vehicle undergoing testing in Arjeplog integrates GKN’s two-speed ‘seamless shift’ gearbox and torque vectoring.
The technology is related to the two-speed technology in last year’s GTD18 Mercedes-AMG GLA 45 test vehicle, which demonstrated the benefits of an eTwinster rear axle e-motor, two-speed eTransmission and torque vectoring by twin clutches — all paired with a mechanical Twinster on the front axle.
The advanced eDrive system in the GTD19 replaces the Jeep Renegade’s internal-combustion engine with a 120kW GKN e-motor that delivers a maximum torque of 3,500Nm and vectoring of up to 2,000Nm to either of the front wheels when required.
Front-wheel-drive applications of torque vectoring provide more noticeable benefits than rear- or all-wheel drive configurations, due to the relative ease of breaking traction in a front-wheel-drive car.
Moreover, the eTwinster system not only keeps the front wheels ‘in check’ during acceleration but also corrects the under-steer yaw moment that drivers can experience when entering a corner at speed (the system prioritises torque delivery to the outer wheel, helping to correct the natural under-steer characteristic typically associated with a front-wheel-drive vehicle).