German automotive supplier ZF has unveiled a new Axle Hybrid concept which uses an electrified Automated Manual Transmission (eAMT). This system combines ZF’s traditional electric axle drive system (eVD) with its automated manual transmission (AMT). The eAMT eliminates tractive force interruption and features AWD capabilities.
“With eAMT, ZF has developed a fully-fledged plug-in hybrid drive for front-transverse vehicles,” says ZF’s electric drive expert Norman Schmidt-Winkel. “This increases flexibility for vehicle manufacturers. They can use existing platforms to implement conventional drives or plug-in hybrids. In some vehicle classes, automatic transmissions are out of the question for reasons of weight, space or cost. In this scenario, the automation of manual transmissions is a great way to significantly increase comfort and efficiency for drivers, as they don’t need to actuate the clutch or change gears.”
ZF says its eAMT’s shift comfort and performance are almost on par with more costly torque converter or dual-clutch transmissions. Normal AMTs experience a tractive force interruption when they disengage in order to engage a new gear. ZF’s new eAMT uses an electric motor on the rear axle to bridge this break with a perfectly timed insertion of torque. “The driver is absolutely unaware of the complex system sequences and control processes running in the background, “says Schmidt-Winkel. “When accelerating, only the benefits of completely jerk-free, powerful acceleration can be felt. Previously, these benefits would only be available in much more expensive hybrid vehicles with more complex transmissions.”