Originally Posted by Bry195

on the surface it might seem like you can’t run an ac motor on a brushless esc but it is done. it can be done with and without sensors or even back emf. early robot servos were permanent magnet motors and the shape of the electricity to rotate these motors was identical to the shape our esc deliver. a bunch of small pulses that simulate an ac waveform. a trapezoid. travel 30 years into the future and those same systems are still dicing up dc but doing a better job of chopping it up and it looks like a sin wave. when a company i worked for discontinued the old (esc) servo drive of 30 years ago auto manufacturer F forced us to design the new systems to work on the old motors because they had 100s of millions in motors buried in every corner of every machine globally. well, the first step was to plug it in and run the old motors on the new sin wave systems and watch what happened. nothing happened except the motors had less torque and ran cooler.

all precision motor controllers take ac and turn it into dc and then chop it up into ac again. im not suggesting that it’s easy but its interesting to know that our hobby is very much connected to some of the highest technology available today.