
IAV has unveiled a new version of its modular electric drive concept at the Vienna Motor Symposium.
Combining electric motor and transmission, it provides up to three speeds and, because of its modular concept, can be made to suit various vehicle platforms and demands. The aim is to combine a high level of ride comfort, efficiency and compact package at competitive cost.
Long-term, electric drive systems will play a key part in mobility because they permit zero-emission mobility and are not reliant on fossil energy. Besides the environmental aspect, manufacturers also need to consider their customers’ demands on ride comfort.
At the same time, consumers expect top efficiency to give them maximum traveling range, good hill-climbing performance, high vehicle speed and good acceleration on one battery charge.
Many of today’s electric drives use a combination of an electric motor and transmission with fixed gear ratio. Although solutions of this type are relatively simple in terms of structure, they cannot meet all of the demands made on them at the same time. For instance, high hill-climbing performance and maximum efficiency demand very different transmission ratios. It is for this reason that IAV has chosen a modular concept based on an electric motor and a transmission with one to three speeds.
Suitable for various powertrain configurations
IAV’s solution is also flexible in terms of use – as the main drive for battery-powered electric vehicles, for fuel cell vehicles or as a component of plug-in hybrids. Its power output is sufficient for vehicles from classes A (subcompact car), B (compact car), C (standard size) and D (upper standard size). It represents a further development of a solution IAV presented back in 2010.
In the modular electric drive unit, an e-motor developed by IAV delivers a continuous power output of 50 kilowatts and maximum power of 80 kilowatts. It generates constant torque of 150 newton meters which can be increased to 300 newton meters for short periods of time. It was designed using IAV’s electric motor synthesis tool which finds the optimum solution for the given application from an almost unlimited number of potential variants.
Providing a maximum of three speeds, the planetary transmission is installed at the side of the electric motor and is capable of generating output torque levels of up to 3,000 newton meters. At the same time, this makes it possible to limit the motor’s maximum speed to 8,000 revolutions per minute. The differential is accommodated in the e-motor, making optimum use of limited package.
Traveling range increased by up to ten percent
Developing the casing also presented a particular challenge. Compact design, a high level of functional integration and temperature management have been combined to provide additional benefits. With IAV’s solution, for example, the power electronics are accommodated in the casing to reduce costs from copper wiring, ensure good EMC shielding as well as include the power electronics in the electric motor’s cooling circuit.
Besides this, the project also placed exacting demands on the casing’s structural stiffness. In developing the casing, IAV’s experts cooperated closely with Nemak, a globally operating aluminum casting specialist. This has resulted in a casing that combines compact size, high stiffness, a high level of functional integration and competitive costs.
Drive unit
– Suitable for vehicle classes A to D
– Hill-climbing ability: maximum of 30 percent
– Top speed: 160 km/h (continuous) / 185 km/h (maximum)
– Acceleration 0 – 60 km/h in 4 seconds, 0 – 100 km/h in 10 seconds
Electric motor
– Power output: 50 kW (continuous) / 80 kW (maximum)
– Torque: 150 Nm (continuous) / 300 Nm (maximum)
Transmission
– Maximum of three speeds
– Torque: 3,000 Nm (maximum)