At the windings, all motors are driven by some alternating waveform. A classic "DC motor" has a mechanical commutator which turns DC into square wave AC, with the phase leading the motor so the motor turns. Classic AC motors are driven from sinusoidal waveforms. There's a whole theory of DC motors, and an elegant theory of AC motors that goes back to Tesla. Here's the motor family tree.[1]
Then came power MOSFETs. Today you can make pretty much whatever waveforms you want. It took a while for motor designers to learn how to exploit that properly, and for MOSFETs to get small, cheap, and heat-tolerant. Then drone and electric vehicle motors got really good, at the cost of needing a CPU to manage the motor.
At the windings, all motors are driven by some alternating waveform. A classic "DC motor" has a mechanical commutator which turns DC into square wave AC, with the phase leading the motor so the motor turns. Classic AC motors are driven from sinusoidal waveforms. There's a whole theory of DC motors, and an elegant theory of AC motors that goes back to Tesla. Here's the motor family tree.[1]
Then came power MOSFETs. Today you can make pretty much whatever waveforms you want. It took a while for motor designers to learn how to exploit that properly, and for MOSFETs to get small, cheap, and heat-tolerant. Then drone and electric vehicle motors got really good, at the cost of needing a CPU to manage the motor.
[1] https://www.allaboutcircuits.com/textbook/alternating-curren...