ZF Stops Development of Solutions for Combustion Engines
Automotive supplier ZF wants to end its development of drive designs for combustion engines and will instead prioritise electromobility.
During a virtual press conference, spokespersons for the automotive supplier ZF, based in Friedrichshafen, explained that the company plans to increase its focus on electromobility with immediate effect. This change in focus will be so substantial that the company will in future no longer develop drive parts for use in vehicles that have only a combustion engine. "We are no longer developing drives for combustion engines; there will no longer be any purely conventional ZF gearboxes," said Dr Michael Ebenhoch, Head of Development of the Car Driveline Technology Division. Ebenhoch went on to explain, however, that hybrids and electric vehicles will continue to exist in parallel for many years to come as both are useful in their fields of application. "The exact distribution is still unclear, and that's why we are fully committed to both options," Ebenhoch said.
In terms of hybrid technology, the supplier is pursuing its ongoing development of plug-in hybrids (PHEVs) that offer significantly increased range in purely electric driving mode compared with previous vehicles. ZF's solution for this is called EVplus, which is now entering its fourth generation. The third generation of the concept car was based on a standard passenger car with an eight-speed plug-in hybrid gearbox from ZF. The mid-size saloon is fitted with a battery with 35 kWh gross capacity. The electric motor integrated into the gearbox provides 65 kW of continuous output and up to 95 kW peak performance, which currently corresponds to the series standard. According to the manufacturer, this means that on a fully-charged battery, the car can travel more than 100 km on electric power alone. Given these kinds of figures are often calculated during testing and in ideal conditions and are therefore viewed somewhat sceptically, the developers have emphasised that this range is possible "in real operation" at any time of the year and while other auxiliary equipment is in active use, such as air conditioning or heating.
Plug-in hybrid with over 100 km range
In the newly unveiled fourth generation of the EVplus, ZF has integrated all of the power electronics into the gearbox casing without increasing the space needed. This means the gearbox can be fitted into existing vehicle designs and is 50% lighter than its predecessor. The most important design change saw the volume for the necessary hydraulics reduced from 3.1 litres to 1.8 litres. This was achieved through the use of direct switching valves. Unlike the electric pressure regulators used until now, these electro-magnetic actuators do not need any additional pistons or bushes. The new EVplus also has improved technical data compared with the previous generation. Its performance has increased from 90 kW and 240 N m of torque to 160 kW at 450 N m in purely electric driving mode. This enables dynamic rides without the use of combustion engines. Ebenhoch had the following to say on his company's "paradigm shift": "The drive is no longer a combustion engine with an electric auxiliary motor: it provides continuous electromobility for everyday driving. Anyone who wants to make a longer journey in the same vehicle can now do so without having to stop to charge and without the risk of being stranded." The fourth generation of the EVplus PHEV drives is due to enter series production in 2022.
As for purely electric vehicles, ZF gave the electric two-speed drive unveiled last year a major boost by increasing the operating voltage from 400 V to 800 V. At 800 V, the charging time can be reduced by a half. A five-minute charge would be enough for a journey of around 160 km. A voltage level of 800 V therefore alleviates the problem of limited range in purely electric vehicles. Ebenhoch announced that the two-speed electric motor has power ratings of up to 350 kW.
At the end of the press conference, the only question remaining was how ZF would fare if combustion engines do in fact overtake e-mobility and experience a resurgence in the event of a possible transition to synthetic fuels. Ebenhoch's response was that the company did not see this as a problem given that its in-house gearboxes are already highly efficient, to the extent that is almost impossible to increase their efficiency.