Thank you for all the replies. What I had in mind is induction motors from 1 HP to 15 HP and applications such as pumps, conveyors, industrial washing machines, etc. where 3-phase induction motors (running at maximum 60 Hz) are used widely with VFD speed control.
By stepper motors I was not referring to close loop stepper / servo motors. So would it give any benefits by replacing with stepper motors?