A voltage limit ellipse is defined in a d-q coordinate system of a rotating electric machine by d-axis and q-axis currents flowing through an armature coil when the magnitude of a voltage vector applied to the armature coil is equal to a voltage limit value. The product of the number of electrical conductor sections per pole in each phase and the number of poles of the rotating electric machine is set to have, when the rotational speed of the rotating electric machine is equal to a maximum rotational speed, the center of the voltage limit ellipse located outside an electric-current limit circle and in a negative d-axis region in the d-q coordinate system and a positive-d-axis-side vertex of the voltage limit ellipse located inside or on the electric-current limit circle.

A rotor for a permanent magnet machine includes first and second axially successive rotor sections each including permanent magnets generating magnetic field having a pole pitch. The rotor includes a first coupling system for connecting the first rotor section to a shaft and a second coupling system for connecting the second rotor section to the shaft or to the first rotor section. The second rotor section is rotatable with respect to the first rotor section by an angle corresponding to the pole pitch in response to releasing the second coupling system so as to set the stator flux-linkages generated by the first and second rotor sections to be substantially zeroes. Thereafter, the permanent magnets do not substantially induce voltages on the stator windings even if the rotor is rotating during for example an internal fault of stator windings.

A vehicle including an engine, a generator, a motor, a driving member and a control device. The generator includes a rotor, a stator having a stator core with a winding wound thereon, and an inductance adjustment device that changes an inductance of the winding by changing magnetic resistance of a magnetic circuit for the winding that passes through the stator core. The current adjustment device adjusts a current outputted from the generator to the motor, which drives the driving member. The control device, upon receiving a request for increasing the current to be supplied to the motor, directs the inductance adjustment device to adjust the generator to operate in a state in which the inductance of the winding is low, directs the engine to increase a rotation speed thereof to increase the rotational power, and directs the current adjustment device to increase the output current of the generator.

A rotating electric machine is configured to include a rotor, a stator that includes a stator core and at least one coil that is wound on the stator core by distributed winding, and a plurality of non-magnetic conductors that respectively forma closed circuit and are arranged in the rotor such that magnetic flux from the stator interlinks an inside of the closed circuit, thereby reducing losses while preventing a decrease of the output torque.

A rotating electrical machine equipped with a magnet unit and a magnetic body. The magnet unit is also equipped with magnet covers wrapped about armature-facing peripheral surfaces of the magnets. Each of the magnets has recesses formed in portions of the armature-facing peripheral surface which are located close to q-axes each of which lies at a boundary between magnetic poles. Each of the magnet covers is recessed in the radial direction in accordance with the shape of the magnet recesses. If the armature-facing peripheral surface of the magnets is between a circumferentially adjacent two of the magnet recesses is defined as a main magnetic pole surface, and an angle representing a circumferential range occupied by the main magnetic pole surface is defined as a main magnetic pole angle ?a, the main magnetic pole angle ?a is selected to be 2?/5<?a<2?/3.

Provided is a variable magnetic flux-type permanent magnet rotary electric machine wherein a leakage magnetic flux leaking from a certain permanent magnet included in the rotor core to a permanent magnet circumferentially adjacent on either side of the certain permanent magnet is controlled by q-axis current and thereby a magnetic flux emanating from the certain permanent magnet and linking with the armature coil wound on the stator is controlled without forming a mechanically weak part in the rotor core.

A rotor structure including a rotor, a stator, and magnetic pole parts is provided. Each magnetic pole part includes a radially-magnetized fixed magnetic-force magnet, first variable magnetic-force magnets which are disposed radially outward of, and at both circumferential end sides of, the fixed magnetic-force magnet, respectively, and have a magnetization state that is changeable in the circumferential direction by a magnetic flux, and a high magnetic-reluctance part formed between the fixed magnetic-force magnet and the first variable magnetic-force magnet in the circumferential direction and having a magnetic reluctance higher than the rotor core. The high magnetic-reluctance part includes a first vertically extending part radially extending at a position near the fixed magnetic-force magnet, a second vertically extending part radially extending at a position near one first variable magnetic-force magnet in the circumferential direction, and a laterally extending part connecting the first and second vertically extending parts in the circumferential direction.

A rotor structure including a rotor, a stator, and magnetic pole parts provided to a rotor core is provided. Each of the magnetic pole parts includes a fixed magnetic-force magnet magnetized in the radial direction, and first variable magnetic-force magnets disposed at both end sides of the fixed magnetic-force magnet in the circumferential direction, respectively. A magnetization sate of each first variable magnetic-force magnet is changeable in the circumferential direction by a given magnetic flux. The first variable magnetic-force magnets are located radially outward of the fixed magnetic-force magnet. A radially outward part of each first variable magnetic-force magnet is held by a respective holding part of the rotor core at a corner part from radially outward. A gap between each holding part and the stator core is wider than a gap between a general outer circumferential surface of the rotor core and the stator core.

A rotor including a rotor core and magnetic pole parts provided therein is provided. The magnetic pole parts are lined up along an outer circumferential surface of the rotor core. Each magnetic pole part includes a fixed magnetic-force magnet with a radially-oriented magnetizing direction, first variable magnetic-force magnets with circumferentially-oriented magnetizing directions, a first cavity part formed in the rotor core to extend between a position radially inward of the fixed magnetic-force magnet and a position radially inward of the first variable magnetic-force magnet, and auxiliary fixed magnetic-force magnets disposed on both sides of the fixed magnetic-force magnet in a circumferential direction so that magnetizing directions thereof are oriented in the circumferential direction. A pole surface with the same polarity as a pole surface facing radially outward of the fixed magnetic-force magnet is located on a fixed magnetic-force magnet side of the auxiliary fixed magnetic-force magnets.

A rotor including a rotor core and magnetic pole parts provided therein is provided. Each magnetic pole part includes a fixed magnetic-force magnet of which a magnetizing direction is oriented in a radial direction, first variable magnetic-force magnets disposed radially outward of the fixed magnetic-force magnet on both sides thereof in a circumferential direction so that magnetizing directions are oriented in the circumferential direction, a first cavity part formed in the rotor core to extend between a position radially inward of the fixed magnetic-force magnet and a position radially inward of the first variable magnetic-force magnet, and a second cavity part formed in the rotor core to be separated radially outward from the first cavity part, and extend toward the first variable magnetic-force magnet in the circumferential direction from a position radially outward of a surface on a first variable magnetic-force magnet side of the fixed magnetic-force magnet side.