Tech Insider / MAGNA ETELLIGENTCOMMAND but also from a design perspective, and that collaboration creates great results.” With the move to high-voltage hybrid systems, there is ever greater commonality between motors developed for BEV and those destined for hybrids, says Dowsett: “The motors in our hybrid transmissions are very similar to those we are using in BEVs, though there are some slight differences due to the compact nature of the DHTs.” The requirements for PHEV motors versus BEV do differ in regard to vibration and thermal conditions, due to the proximity of the engine. This is reflected not only in the mechanical design of the electric machines but also in the calibration of the ICE to ensure as smooth an operation as possible. There are also some differences in the detail design, not least because the operating RPM of a hybrid is generally lower than a BEV. “You have slightly lower speeds, though we are trying to improve that by balancing the motor operating points against the gearset,” notes Dowsett. “However, the OEMs tend to dictate the ratios.” 1 MANUFACTURING EDGE There are distinct advantages to using what are essentially BEV motors in PHEV applications, particularly the manufacturing flexibility such an approach provides. Some manufacturers are scaling back their near-term BEV plans, with a knock-on effect on production lines. Being able to keep the same lines running for PHEVs is advantageous: “Once you have tooled up a production line for BEV, it makes sense to fully utilize it,” says Dowsett. Magna has made a point of incorporating the latest technologies into its PHEV motors, such as hairpin windings. As Dowsett says, “We’re continuing to evolve the way that we wind and the number of layers in the motor, and our models that can simulate power density and torque and speed are getting better and better. But we have to make sure we can manufacture them. So we do all that work up front and share it with LG Magna; they are constantly working on the development of refinements to the windings.” 2 Our models that can simulate power density, torque and speed are getting better and better. But we have to make sure we can manufacture them” Not only do hairpin windings bring advantages in terms of fill factor, they also net production benefits. “When using round wire, you need operators to push all the windings over; with hairpins, that need is eliminated,” explains Dowsett. He also suggests that the company has considered bringing motor laminate production in-house, as other arms of the company have extensive experience in advanced metal stamping techniques. With ever more complex stampings needed as engineers chase efficiency, there could be advantages in having further vertical integration of production. “Magna is looking very closely at whether we should make laminations ourselves. We have all those stamping skills under the Magna umbrella and while there are a lot of people stamping laminates, we think we might have some innovations to bring.” 1 & 2. HYBRID DRIVE Magna’s DHD packages a 5-speed transmission, motor and inverter SUSTAINABLE PRODUCTION Like most motor manufacturers, Dowsett and his team are also working hard on reducing the need for rare earth materials in their PSMs. “We’re getting close to eliminating dysprosium,” he reveals. However, this brings new challenges, not least a reduction in 14 www.automotivepowertraintechnologyinternational.com / March 2025
Automotive Powertrain Technology International Automotive Powertrain Technology International March 2025 Issue: Page 14
