Patent ID: 9735660
Date: 2017-08-15
CPC Classifications: H02K

Claim:
1. A rotary electric machine comprising: a rotor including a rotor core fixed to a rotary shaft so as to be rotatable together with the rotary shaft, and multiple pairs of embedded magnets fixedly embedded in the rotor core and magnetized such that magnetic poles of the embedded magnets in each pair, the magnetic poles being opposed to each other in a circumferential direction of the rotor, have the same polarity; a stator including a stator core having teeth opposed to rotor magnetic pole portions each interposed between one of the pairs of the embedded magnets of the rotor core, and coils wound around the teeth; a control device that causes the stator to generate a rotating magnetic field by supplying electric power to the coils; and a magnetic flux supply element supported by the rotary shaft so as to be rotatable relative to the rotary shaft, and having supply element magnetic pole portions formed by auxiliary magnets fixed to the magnetic flux supply element, wherein a relative rotation angle of the magnetic flux supply element relative to the rotor during rotation of the rotor is (i) allowed to be held at a weakening angle at which a polarity of each of the rotor magnetic pole portions and a polarity of the supply element magnetic pole portion opposed to the rotor magnetic pole portion are opposite to each other, and wherein magnetic flux of the rotor decreases and the rotor is permitted to rotate at high speed, and (ii) allowed to be held at a strengthening angle at which the polarity of each of the rotor magnetic pole portions and the polarity of the supply element magnetic pole portion opposed to the rotor magnetic pole portion coincide with each other, and wherein the magnetic flux of the rotor increases and the rotor is capable of generating high torque, the control device controls a d-axis current to the coils of the stator, the d-axis current being a current in a direction of a magnetic flux of the rotor, and the control device is selectively operable to change the relative rotation angle of the magnetic flux supply element (a) from the weakening angle to the strengthening angle, and (b) from the strengthening angle to the weakening angle.