GKN Automotive is developing the world’s first battery electric vehicle (BEV) with a two speed transmission and torque vectoring on the front axle. Based on a Jeep Renegade, the GTD19 demonstrator vehicle is undergoing extensive testing at GKN’s annual winter testing programme in Arjeplog, Sweden, and showcases how automakers 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 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 exceptional stability and dynamic performance is possible thanks to the torque vectoring capability of GKN’s eTwinster system.
Hannes Prenn, COO of GKN ePowertrain commented: “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 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 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; paired with a mechanical Twinster on the front axle.
The set-up in GTD19 provides pure electric power with two-speeds. The electric two speed gearbox is configured to ensure the shifts are seamless, with minimal losses in power and torque and the potential for faster acceleration, improved efficiency and a higher top speed.
The advanced eDrive system in the GTD19 replaces the Jeep Renegade’s internal combustion engine with a 120kW GKN e-motor, delivering 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. Not only can the Twinster system keep the front wheels in check during acceleration, it can correct an understeer yaw moment experienced by a driver entering a corner at speed. The system prioritises torque delivery to the outer wheel helping to correct the natural understeer characteristic typically associated with a front drive vehicle.