Standard motors feature an internal rotor that spins inside of a stator.
This offers a distinct advantage over conventional induction motors that may stop completely if a power interruption lasts over a second. The machine features a rotor surface design that includes a continuous layer of magnetic material. The stator windings are similar to those of a conventional induction motor except that an additional concentrated winding is added to form a writer pole. Excitation is discontinued when synchronous speed is reached, but is automatically reapplied if the rotor slows down under excessive load. The machine's unique design allows the motor to begin operation with a very low start-up current and to gradually increase RPM's up to a synchronous speed.