Induction electric motors have almost intermittent speed and low-power induction motors are mostly single-phase, short-rotor motors and starters require special devices since they do not have their own starters. It features changeable speed.
In the motor to the repulsion the winding of the rotor is taken to the brushes that are interconnected in short circuit and presents variable speed, being thus it is applied quite often like engine of repulsion induction. At start it operates as a repulsion motor and has its own start and, later, a centrifugal device, where the slides of the collector are short-circuited, starting to work as a single-phase induction motor reelcraft S24-260044.
The three-phase induction motors are high-power and self-starting. Since they require a large network current, at their starting point, special devices are applied to reduce it. In series or universal single-phase motors the rotor winding is fed to the brushes through a switch (collector formed by separate blades) and connected to the stator. This type of motor operates on both direct and alternating current.