Method and device for starting megawatt-level double-fed motor

TL;DR: In this paper, a method and device for starting a megawatt-level double-fed motor is presented, where a frequency converter at a rotor side of an existing double-feed motor is utilized to control a rotor current (voltage) to generate rotating magnetic fields.

Abstract: The invention provides a method and device for starting a megawatt-level double-fed motor A frequency converter at a rotor side of an existing double-fed motor is utilized to control a rotor current (voltage) to generate rotating magnetic fields, so that stator windings which are subjected to short circuit by a stator short-circuit contactor generate an induced current and stator fields, thus the motor generates electromagnetic torques to drive rotors to rotate, thereby realizing zero-speed start of the double-fed motor In the invention, the frequency converter at the rotor side of the existing double-fed motor is utilized to realize flexible start of the motor, and the stator short-circuit contactor is added Compared with a rotor series resistance method or stand-by motor dragging method and the like, the method provided by the invention is low in cost, and has no impact on a power grid Because only one stator short-circuit contactor is added, the system structure is simple, the processes of motor startup, synchronization and speed adjustment are simple without the impact cohesion, and are automatically and completely controlled by a converter, thus the complete automation is realized and the reliability is high