Global drivetrain and suspension manufacturer ZF Group is moving into the hybrid-drive arena in a big way, according to Wolfgang Vogel, member of the Board of Management of ZF and group executive of the Commercial Vehicle and Special Driveline Technology Div.
“Value [to ZF] means fuel economy plus reduction of emissions and waste as well as safety and the security and comfort of the driver. [With all that in mind] we have a full line of hybrid solutions under development — especially suited for stop-and-go trucks and buses,” said Vogel, speaking at a media conference held last month by the Friedrichshafen, Germany-based supplier at the famed Nurburgring racetrack near Cologne.
The company's ZF Group North American Operations, based in Northville, MI, supplies drivetrain and suspension components to North American automotive and truck OEMs and operates the ZFMeritor joint venture with ArvinMeritor that supplies FreedomLine automated manual transmissions here.
“ZF offers hybrid technology solutions ranging from the electric motor to complete hybrid systems for trucks and buses,” added Vogel. “Different concepts [are necessary] depending on vehicle applications and customer requirements.”
According to Vogel, “distributor trucks,” delivery vans and city buses in particular can benefit from hybrid technology. Therefore, he said, besides manual and automatic transmission systems, ZF will also offer hybrid variants in the future.
Commercial vehicles used in local service, such as delivery trucks, equipped with hybrid powertrains that encounter considerable start/stop operation can save considerable amounts of fuel, he explained. During start/stop operation, the combustion engine is switched off at standstill and, upon request, re-activated by a quick start of the electric motor.
Vogel explained that current volume production development projects are for the HyTronic (the hybrid version of the AS Tronic lite automated manual) and a hybrid transmission based on its eTronic transmission. Both of these variants are parallel hybrid — where an electric motor and the combustion engine are connected in parallel via a transmission. Since this concept taps existing resources in the driveline, he noted it can be “implemented in a particularly economical way.”
What's more, according to ZF, the parallel hybrid concept is flexible enough that it can be used to produce both “mild” and “full” hybrids, which use the entire range of hybrid functions: the start/stop function, regeneration of braking energy (recuperation), support during acceleration (boosting), electric starting, and purely electric driving. Full hybrid systems may use up to 30% less fuel in city traffic, the company noted.
ZF also said the advantage for OEMs already using its transmissions is that all ZF hybrid variants, based on the parallel hybrid concept, “can be integrated into existing drivelines like manual or automatic transmission systems.”
Although it had little officially to say about it, ZF did show off a Mercedes-Benz Sprinter hybrid van under development for Germany's Daimler AG.