Quietly and eco-friendly through the city
Ziehl-Abegg presents the ZAwheel Electric wheel-hub drive at the IAA for Commercial Vehicles
"We are putting the invention of our company founder Emil Ziehl – the external rotor motor – on the road as the ideal mobility solution for commercial vehicles" declares Ralf Arnold, Managing Director of Ziehl-Abegg Automotive. The South German company is presenting a gearless wheel-hub drive (ZAwheel) for commercial vehicles at the IAA. It boosts efficiency to 90 percent as compared with the 20 to 30 percent efficiency of combustion engines.
Ziehl-Abegg is applying its more than 100 years of experience in the construction of electric motors. In the past such drives could be found in elevator motors, in fans and in special vehicles. "Our goal has always been to reduce the energy requirement, to minimise the operating noises and to construct high class motors that perform their duties lastingly and reliably" Arnold explains. So together with partners the gearless wheel-hub drive was also exhaustively scrutinized and tested for many years in scheduled service use in various countries in field trials before deciding in favour of the market launch at this time.
Consequently, the statements made on consumption and efficiency are based on verified measurements. "We have cut the energy consumption in half as compared with buses using combustion engines" the motor expert Arnold emphasizes. The fact is that combustion engines achieve an efficiency of just 22 to 30 percent. A conventional electric motor with a frequency inverter reaches 85 percent – "and we increase the efficiency to even 90 percent" says Arnold. That is possible because in the ZAwheel shift, differential, or simple reducing gears are no longer needed. And that is because the motor sits in the middle of the wheel. Of course it goes without saying that the energy does not get lost during braking; rather it is fed back into the battery. "It is exactly in commercial vehicles such as city buses, which have to start and brake often, that the efficiency is especially reaped through the energy recovery" Arnold underscores. On top of that road users, passengers and residents are spared 90 percent of the traffic noise. "A significant plus in life quality."
ZAwheel can be integrated into new or used buses. To accomplish that the entire drive train is replaced with the ZAwheel-axle unit and the necessary electrification is undertaken.
Background
Already back in 1897, Emil Ziehl had the idea of letting a motor revolve around a fixed stator. This external rotor motor is state of the art in many areas. That is also the case in the fan sector where Ziehl-Abegg has been the technology leader for decades. And now Ziehl-Abegg is implementing this development in electromobility for commercial vehicles as an extremely sustainable solution.