Motor system provided with both motor having multiple-phase stator windings and control device controlling the motor

A motor system comprising:

• a motor;
• and
• a control device,
• wherein the motor comprises
• a stator having a circumferential direction and an axial direction, the stator having a circumferential periphery along the circumferential direction;
• a rotor having a circumferential direction, the rotor having a circumferential periphery along the circumferential direction of the rotor and being opposed to the circumferential periphery of the stator via an air gap;
• multiple-phase stator windings arranged at the stator, the stator windings being windings of multiple phases to which multiple-phase AC currents are supplied as stator currents, the windings of multiple phases being arranged, phase by phase, at predetermined circumferential pitches at the circumferential periphery of the stator, the stator currents passing along the axial direction in the circumferential periphery;
• and
• a rotor winding arranged at the circumferential periphery of the rotor along the circumferential direction, the rotor winding being supplied with a rotor current;
• the control device comprises:
• a stator current supplying circuit which supplies the stator current to each of the stator windings for drive thereof;
• a rotor current supplying circuit which supplies the rotor current to the rotor winding for drive thereof, the rotor current being transmitted from a fixed part of the motor system to a rotor side;
• and
• a current control circuit which controls both the stator currents to the stator windings and the rotor current to the rotor winding,
• wherein the current control circuit is configured to control such that
• the stator currents are substantially synchronized with rotation of the rotor,
• the stator currents and the rotor current each include mutually opposed currents whose flowing directions are relatively, in part or in all of the currents, opposite to each other in the axial direction, and
• a sum of torque current components generated by the stator currents at the stator and a sum of torque current components generated by the rotor current at the rotor are equal, the torque current components at the stator and the torque current components at the rotor being approximately mutually opposed via the air gap.