Monday, May 20, 2013

ZF Presents Electric Drive And All Wheel System Abkoppelbares

ZF Electric Vehicle Drive 1 (ZF EVD1) based on the Stromos of German E-Cars
ZF Electric Vehicle Drive 1 (ZF EVD1) based on the Stromos of German E-Cars



On the track, "Circuit Ricardo Tormo" in Valencia was a small group of car and motor sport journalists learn on Tuesday this week as part of a Technical Workshops two premieres of ZF: An electrical axis module and a abkoppelbares wheel-drive system.

The system, designed for small and mid-sized cars in the electrical axis module is Stromos of German E-Cars built (based on the Suzuki Splash). The disconnectable wheel drive system eConnect for front-transverse passenger cars - in the Land Rover Freelander 2 performs his work.

"Our electric axle drive designed for future needs in urban transport," Dr. Hans-Jörg Domian, manager explained predevelopment construction at ZF. With 90 kW of electric power and high torques is centrally positioned on the axis of the drive module develops already at low speeds, the acceleration potential heavy motorized combustion engines.

The 45-pound drive consists of an asynchronous electric motor, a compact catchy translation unit, power electronics and control software - everything from ZF. "With our innovative high-speed concept (larger 21,000 rev / min: editors note), we were able to more than offset the weight disadvantage of induction motors at low speeds compared with a permanent magnet synchronous motor," said Domian. The result is a cost effective system with high efficiency in typical driving cycles of an electric vehicle. It connect high performance with reduced material usage.

The drive already unfolds when starting a torque of 1400 Newton-meters of the vehicle axle. In order to accelerate from 0 takes to 100 km / h in nine seconds. The maximum power of 90 kW is available for 1 to 1.5 minutes. The constant output is 30 kW. Furthermore, according to Dr. ZF could Domian by the optimum combination of electric motor and power electronics to win up to six percent range.
Abkoppelbares car wheel-drive system

The wheel system eConnect is especially suitable for four-wheel vehicles with front-transverse drive as the new 9-speed automatic transmission (9HP) ZF: In 2WD front operation is the entire wheel drive train to a halt - the angle drive on the propeller shaft through to the rear. Automatic disconnection takes forward immediately after the main gearbox and the rear axle via a respective coupling place for the left and the right wheel. So at the wheel components, there are no consumption increasing drag losses. Fuel-efficient is the effect of the weight-optimized design of the all-wheel system: Overall, there are up to five percent savings. The activation and deactivation of the four-wheel drive takes a few hundred milliseconds, the driver almost imperceptibly.

In addition to the fuel savings, the system also offers driving dynamics advantages: The two clutches on the rear axle allow free cross-distribution of torque between the left and right rear wheels. So it is about the classic hang-on approach (demand torque distribution between front and rear axle) also possible to use the effect of the torque Vectoring: Here is the yaw moment of the vehicle actively influenced by a wheel-specific control of the rear wheels. Improve on changing surfaces or in corners so simultaneously traction and stability.

Was rounded off the set-up of IF test vehicles by IWD (Intelligent Wheel Dynamics). In the test carrier based on a BMW 3 Series Touring with all-wheel drive systems are active in the drive, cross-linked to the steering and suspension and centrally controlled. "IWD brings same dynamics with greater margin of safety or the same safety margin to more dynamics," concluded Dr. Domian.

Land Rover Freelander 2
IF eConnect: abkoppelbares car wheel drive system in the Land Rover Freelander 2

BMW 3 Series Touring
IF IWD (Intelligent Wheel Dynamics) - a test carrier based on a BMW 3 Series Touring with all-wheel drive.

the Electric Vehicle Drive 1 unfolds from start-up
The drive in the Electric Vehicle Drive 1 unfolds from start-up torque of 1,400 Newton meters on the vehicle axle

Core of the electric axle drive is an electric motor with 90 kW peak power and an integrated translation unit
Core of the electric axle drive is an electric motor with 90 kW peak power and an integrated translation unit