The windings receive current through some kind of slip-ring arrangement. Once the rotor ... Power is applied to coils wound on stator teeth ... Unlike induction motors, there are no rotor bars and ...

Shown is a close-up of the slip-ring assembly that powers the rotor of the motor used in BMW's iX-M60 electric SUV. The vehicle uses a pair of these slip-ring-energized WRSMs, with a 255-hp front ...

The squirrel-cage induction motor has been ubiquitous for over 100 years, and wound-field DC or universal motors were the norm in power tools and car starter motors until really rather recently.