Understanding rotating frequency converters makes repair easier
The poles for the stator and rotor of the wound-rotor motor must be equal. When rewinding any wound-rotor motor, watch for consequent-pole connections. Grouping alone is not a reliable indicator of poles. The best way to understand the process is to visualize the rotating electrical field in the stator of a wound-rotor motor. The field rotates one direction, so that when the rotor is driven in the opposite direction the passing frequency is increased. If the speeds are the same (i.e., the same number of poles as the drive motor) the output frequency will double.