Abstract: A method of controlling a motor having windings of a plurality of phases includes an estimation step of calculating a current vector norm from d-axis current and q-axis current flowing in the motor, calculating power loss from the current vector norm and the entire heat resistance of the motor, and estimating the maximum temperature of the windings of the plurality of phases based on the power loss and a transfer function having first or higher-order transfer characteristics, in the case where the motor is in a low rotation state, and a limiting step of limiting input power based on the maximum temperature estimated in the estimation step.

Abstract: A method of controlling a motor having windings of a plurality of phases includes an estimation step of calculating a current vector norm from d-axis current and q-axis current flowing in the motor, calculating power loss from the current vector norm and the entire heat resistance of the motor, and estimating the maximum temperature of the windings of the plurality of phases based on the power loss and a transfer function having first or higher-order transfer characteristics, in the case where the motor is in a low rotation state, and a limiting step of limiting input power based on the maximum temperature estimated in the estimation step.

Abstract: A magnet evaluation device is provided for evaluating a magnet having at least two magnetic pieces bonded to an insulating material sandwiched between two adjacent ones of the magnetic pieces. The magnet evaluation device has an excitation coil and a detection coil. The excitation coil is configured to generate a magnetic field that has a size in a range that corresponds to a region including the insulating material. The detection coil has a coil diameter that is smaller than a length of one of the magnetic pieces in a direction in which the magnetic pieces are aligned.

Abstract: A rotor structure for an electric rotating machine has a rotor, a plurality of strip-shaped permanent magnets which are arranged in a circumferential direction of the rotor, each of which penetrates the rotor in an axial direction of the rotor, flux barriers which are air gaps provided at positions corresponding to width-direction end portions of the permanent magnets to face the width-direction end portions of the permanent magnets, and demagnetization prevention holes, each of which is provided at a position in a vicinity of a corresponding one of the flux barriers and on an opposite side of the flux barrier from a stator and configured to reduce demagnetization at a corresponding one of the width-direction end portions of the permanent magnets.

Abstract: A rotor structure for an electric rotating machine has a rotor, a plurality of strip-shaped permanent magnets which are arranged in a circumferential direction of the rotor, each of which penetrates the rotor in an axial direction of the rotor, flux barriers which are air gaps provided at positions corresponding to width-direction end portions of the permanent magnets to face the width-direction end portions of the permanent magnets, and demagnetization prevention holes, each of which is provided at a position in a vicinity of a corresponding one of the flux barriers and on an opposite side of the flux barrier from a stator and configured to reduce demagnetization at a corresponding one of the width-direction end portions of the permanent magnets.

Abstract: A flux barrier includes a radially outer proximate part and a radially inner proximate part that are a rotor radially outer side surface and a rotor radially inner side surface extending from a communicating part, at least one of the radially outer proximate part and the radially inner proximate part is connected to an end part of a magnet fixing part of a magnet hole in an inward direction of the magnet hole, and a projecting part projecting in an inward direction of the flux barrier is provided on at least one of the radially outer proximate part and the radially inner proximate part connected to the magnet fixing part. A constricted part in which a width of the flux barrier is narrower than on a side closer to the communicating part than the projecting part is formed by the projecting part.

Abstract: A magnet evaluation device is provided for evaluating a magnet having at least two magnetic pieces bonded to an insulating material sandwiched between two adjacent ones of the magnetic pieces. The magnet evaluation device has an excitation coil and a detection coil. The excitation coil is configured to generate a magnetic field that has a size in a range that corresponds to a region including the insulating material. The detection coil has a coil diameter that is smaller than a length of one of the magnetic pieces in a direction in which the magnetic pieces are aligned.

Abstract: A flux barrier includes a radially outer proximate part and a radially inner proximate part that are a rotor radially outer side surface and a rotor radially inner side surface extending from a communicating part, at least one of the radially outer proximate part and the radially inner proximate part is connected to an end part of a magnet fixing part of a magnet hole in an inward direction of the magnet hole, and a projecting part projecting in an inward direction of the flux barrier is provided on at least one of the radially outer proximate part and the radially inner proximate part connected to the magnet fixing part. A constricted part in which a width of the flux barrier is narrower than on a side closer to the communicating part than the projecting part is formed by the projecting part.