I have a fairly solid background in industrial AC motor control (soft starters, VFDs, etc.) but something that I'm certainly NOT well versed in is brushless DC motors… the type found in every hard drive on the planet.
As far as I can tell, they look identical to your typical star-connected AC induction motor, and the motor controllers look to be very, very similar to the typical three-phase AC controllers I've spent most of my professional life designing.
I can't find much on the real differences between the two, neither from a mechanical construction point of view nor from a control point of view. The closest I seem to find is "they're similar."
Does anyone have any resources or can offer a fairly technical explanation of what the major differences between these types of motors is and their control methods?