When it comes to electric vehicle (EV) powertrains, AC and DC motors are seen by many as sole competitors as the two have diverse and often mutually exclusive applications. DC motors, for example, are much more robust and easier to control, capable of delivering high torque at lower speeds and keeping the price threshold low for manufacturers.
However, the large size, low efficiency and high maintenance requirements make AC more attractive to some manufacturers and suppliers. In contrast, AC motors are highly efficient and reliable, maintain regenerative capacities for battery management and require less maintenance. Despite DC being a far more mature technology, automakers and Tier 1 suppliers are investing heavily in both types of motors, scouting improved efficiency and reliability at a lower cost.
While the differences between AC and DC technology may seem stark, Nabeel Shirazee, US-based ePropelled’s Co-founder and Global Chief Technology Officer, says that comparing the two is ultimately “irrelevant.” An e-motor manufacturer that has been in operation since 2018, ePropelled been developing an expansive influence over the e-motor sector through its work in the aviation industry and more recently its partnership with Lotus to develop a new torque-switching motor.
The irrelevance of comparison, explains Shirazee, is because the same key considerations—namely heightened efficiency, increased reliability, and lower prices—apply to both sides. With current developments being driven by price and material availability, “both AC and DC motors need to coexist if they want to remain profitable,” Shirazee explains. He adds that as manufacturers look to cut costs, “the evolution of AC and DC motors will remain closely linked through joint development across all different EV platforms.”