Why using universal, high frequency or SR motors?
Basically between a standard three phase motor and the high frequency motor is not a big difference concerning the motor design. Both motors have a multi slotted stator with a three-phase two-pole or four-pole winding and a cage rotor. The SR motor is a new designed motor generally fitted with a four-pole stator and a four-pole or two-pole rotor. The universal motor is the most used motor, integrated in devices from a 10W shaver up to a 3500W power tool. The table below shows the specific details for the different motors.
