Two great minds in permanent magnet-free motor design combine their know-how to create an even more capable inductive electric motor. Mahle and Valeo have teamed up to introduce what they call the Inner Brushless Electrical Excitation (iBEE) system, a form of e-machine that eliminates the need for sensitive rare earth metals, promises powerful performance and reduces carbon emissions over the life cycle of a large, down a steep slope. cliff.

We’ve been closely following Mahle’s work in permanent magnet-free motors since it developed a cheaper, more efficient motor design free of rare earth elements in 2021. The German automotive supplier uses wireless induction with a rotor configuration they call the Magnet-Free Contactless Transmitter (MCT).

The MCT system replaces the physical magnets and mechanical brush-driven electromagnetic windings commonly used in motor rotor designs, with wound coils that are magnetized via inductive electricity sent by a wireless transmitter. This setup not only eliminates the dependence on rare earths, and the supply, mining and pricing issues that come with them, but also reduces the physical wear and tear and necessary maintenance associated with physical brushes. Mahle says the MCT format also allows for more compact packaging thanks to the use of fewer components.

French automotive supplier Valeo has in turn focused on magnet-free electric motor stators and control systems, working with Renault on its next-generation E7A motor design, scheduled for 2027. The energy-dense hairpin copper winding technology is an integral part of the E7A’s stator design.

Mahle

The new joint development agreement between the two companies will combine Mahle’s magnet-free rotor technology with Valeo’s inverter and motor control technology to create an even more advanced evolution of magnet-free motor design for high-end vehicles. The new iBEE axle will offer a power range between 220 and 350 kW (295 and 469 hp).

Mahle and Valeo also plan to work on an engine cooling system aimed at achieving a superior continuous to peak power ratio. Mahle has used an oil cooling system as the backbone of its SCT engine, the ‘endurance champion’ that blurs the line between peak and continuous power by running continuously at more than 90% peak power. Although the original SCT motor used permanent magnets, it was also designed to work with the inductive MCT layout.

The two companies aim to reduce the overall CO2 footprint by more than 40% compared to a permanent magnet e-motor of equivalent power. That is a further improvement on the 30% reduction target from Valeo and Renault’s work on the E7A engine.

Valeo and Mahle plan to complete initial testing of the prototype by the end of 2024.

Source: Mahle/Valeo