New magnet-free electric motor boosts EV power, cuts CO2 emissions
Two companies have collaborated to expand the product range of magnet-free electric motors to upper-segment applications. Valeo and MAHLE will develop an innovative magnet-free electric axle system, targeting upper-segment electric vehicles with peak power ranging from 295 to 469 hp (220 kW to 350 kW). Valeo’s technology is based on the successful joint development of magnet-free electric motor technology (EESM–Externally Excited Synchronous Motor) with a European OEM, according to the company.
Cutting-edge technology can boost efficiency of magnet-free electric motors
The companies are introducing an inner Brushless Electrical Excitation (iBEE) system, a cutting-edge technology[1] that they claim can revolutionize the performance and efficiency of magnet-free electric motors.
“This cooperation with MAHLE is a perfect match. MAHLE develops the EESM rotor and their brushless excitation system,” said[2] Xavier Dupont, Valeo Power Division CEO. Dupont highlighted that Valeo provides dedicated control[3] of this electric motor and brushless system embedded in the inverter.
This partnership allows Valeo to complete its EESM portfolio towards upper segment and is key to support the evolution of the automotive industry towards more innovative sustainable solutions, according to Dupont.
Innovative cooling concept to be developed
Both companies[4] have signed a Joint Development Agreement to combine both Valeo’s expertise in electric motors, highly efficient inverters[5] and associated motor control laws and the expertise of MAHLE on magnet-free rotor with its MAHLE Contactless Transmitter (MCT) technology. The companies are working on an innovative cooling concept in order to achieve an outstanding continuous to peak power ratio. Moreover, the carbon footprint is expected to be reduced by more than 40% versus a permanent magnet electric[6] motor of equivalent power, said the companies in a press release.
First prototypes expected to be completed by end of 2024
The testing of the first prototypes is expected to be completed by the end of 2024.
The first EESM development by Valeo is based on a cooperation with a European OEM launched in 2022 in order to create a new magnet-free electric motor generation (EESM). The company maintained that the initial targets of the project were double; first to get an all-in-one architecture with a new stator and cooling technology in order to increase by 30% the power density compared to the current motors equipping the current OEM’s vehicles on the road. Secondly, to shrink its carbon footprint by 30% vs. an electric motor equipped with magnets (PMSM).
The company also claimed that a validation phase for more than 6 months was successfully ended with results level over the initial expectations in terms of power and efficiency especially thanks to Valeo inverter expertise. “The performances are matching the level of permanent magnet electric motors for B/C segment vehicles with all benefits of a magnet-free technology (no rare earth, lower carbon footprint…),” said[7] Valeo in a press release.
Electric drive systems
MAHLE claimed that it has been focusing on developing electric drive systems. Its contactless transmitter technology for magnet-free electric motors is claimed to be the key enabler for the next evolution of EESM based e-axles.
The company stressed that avoiding the use of rare earth materials not only positively contributes to the sustainability of e-mobility but is also advantageous in terms of costs and resource security. The key feature is the inductive and thus contactless and wear-free power transmission, allowing motor operation at benchmark efficiency level, according to MAHLE[8]. Martin Wellhoeffer, Member of the MAHLE Group Management Board, stated that the new e-axle will benefit from MAHLE’s expertise in contactless transmitter technology.
“Together we will be setting a new benchmark in packaging and efficiency for EESM based e-axles and taking the next step for our customers towards future mobility”, said Wellhoeffer.
[embedded content]