eDrive for plug-in hybrids promises efficiency and power in single package

The eDrive system, which is smaller and lighter than existing electric drivelines, will allow carmakers to buy a single module, rather than having to source and integrate different components together.

The module integrates a water-cooled electric motor and inverter, with a single speed eAxle reduction gearbox.

By integrating the various elements of an electric driveline into a single – smaller - package, the technology can improve the overall system’s efficiency and power density, according to Andreas Mair, all wheel and electric drive senior director of product technology (mechanical) at GKN Driveline.

“Typically if I reduce the packaging then I lower the weight, and for electric and hybrid vehicles in particular, weight is a very important topic,” said Mair. “Since the energy is coming from the batteries, the efficiency of the whole drivetrain is something that we have to look at very carefully.”

The complete module measures 300mm high and 325mm wide, and weighs 54kg, making it around 20mm narrower and 2.5kg lighter than comparable systems.

This also gives carmakers more options for packaging and assembling the driveline, said Mair. “If I have three individual components then I have three different housings, so if I can get rid of some of the interfaces [between them] because I have put three or four things together, then obviously I’m better off for space.”

The module is also the first eDrive system to replace external wiring with a busbar, a copper strip designed to carry large electric currents over short distances. This results in a system with higher power density that is easier to install, the company claims.

The entire eDrive system generates up to 65kW of power, and can transmit up to 2,000Nm of torque to the rear wheels.

Carmakers are increasingly looking to integrate more features into all-electric and plug-in hybrid cars, according to Rainer Link, all wheel and electric drive vice president business development director at GKN Driveline.

“With electrification car makers want to bring more features into the car, and still maintain the fun to drive element,” he said.