Abstract: An electric machine includes a stator having a stator core, rotor core and/or magnetic core comprising a plurality of slots. Each of the plurality of slots includes a spacer, a conductor, and encapsulated slot insulation. The spacer is configured to suspend the conductor away from the stator core by a dielectric distance without occupying all of the space between the conductor and the stator core. The encapsulated slot insulation includes an encapsulation material configured to flow in a liquid state around the perimeter of the conductor filling in the space between the conductor and the stator core. The encapsulation material cures to hold the spacer and the conductor in place. The encapsulated material typically has higher thermal conductivity properties than a conventional slot liner, increasing the performance of the motor.

Abstract: The present disclosure provides a brushless permanent magnet machine which includes an essentially circular shaped rotor, and a pair of magnets arranged in the rotor. The magnets are each U-shaped and have a thickness direction extending along a contour of the corresponding magnet between the opposite poles of the corresponding magnet, respectively. The magnets are each composed of a non-rare earth material having a lower coercivity than a rare earth material. A direction of magnetization of each of the pair of magnets is parallel to the thickness direction of the corresponding magnet. The present disclosure also provides a method of manufacturing such a brushless permanent magnet machine.

Abstract: A rotor for a permanent magnet electric motor includes a rotor core having a generally cylindrical shape with an outer circumferential surface and a rotational axis and a plurality of magnet insertion hole arrangements formed in the rotor core and arranged circumferentially at a preset angular interval about the rotational axis. Each hole arrangement has a radially inward side, a radially outward side, and two ends that are respectively spaced apart from the circumferential surface by respective bridge regions formed by the rotor core. The material of the bridge regions is metallurgically transformed by having its grain structure changed, e.g., by heating the material to at least its Curie temperature, whereby the material possesses greater magnetic reluctance than the material of adjacent portions of the rotor core.

Abstract: The present disclosure provides a brushless permanent magnet machine which includes an essentially circular shaped rotor, and a pair of magnets arranged in the rotor. The magnets are each U-shaped and have a thickness direction extending along a contour of the corresponding magnet between the opposite poles of the corresponding magnet, respectively. The magnets are each composed of a non-rare earth material having a lower coercivity than a rare earth material. A direction of magnetization of each of the pair of magnets is parallel to the thickness direction of the corresponding magnet. The present disclosure also provides a method of manufacturing such a brushless permanent magnet machine.

Abstract: A rotor for a permanent magnet electric motor includes a rotor core having a generally cylindrical shape with an outer circumferential surface and a rotational axis and a plurality of magnet insertion hole arrangements formed in the rotor core and arranged circumferentially at a preset angular interval about the rotational axis. Each hole arrangement has a radially inward side, a radially outward side, and two ends that are respectively spaced apart from the circumferential surface by respective bridge regions formed by the rotor core. The material of the bridge regions is metallurgically transformed by having its grain structure changed, e.g., by heating the material to at least its Curie temperature, whereby the material possesses greater magnetic reluctance than the material of adjacent portions of the rotor core.

Abstract: A distributed generation power system includes a utility meter connectable to an electric utility provider and configured to communicate with a communication device of the utility provider, an inverter configured to convert distributed generation (DG) power generated by a DG power source into AC power, and an intermediate connector configured to connect the meter and inverter to constitute an integrated inverter-meter. The integrated inverter-meter is configured to communicate a measured aggregate amount of the DG power and a measured amount of power consumed on site to the communication device of the utility provider. The inverter is configured to receive at least one operating command from the meter and/or the communication device of the utility provider.

Abstract: A stator of an electrical machine operable as a motor or a generator, applicable to a radial-axial type machine. The stator includes a plurality of stator segments disposed circumferentially about an axis. Each segment has a generally wedge shaped core and a winding wound around the core. The winding is bent to have portions that are disposed on multiple planes. The core includes an elongated wedge tip portions aligned parallel to the axis and an outer radial face opposite to the tip portion. The multiple planes include at least one plane substantially normal to the axis and at least one plane tangential to the radial face.

Abstract: A rotor includes a cylindrical rotor core having an outer circumferential surface and a plurality of magnet insertion holes formed in the rotor core and arranged circumferentially at a preset angular interval about the rotational axis of the rotor core. Each hole extends in a direction parallel to the rotational axis and has a cross section of a generally elongated slit. The elongated slit is curved concave relative to the circumferential surface and has a radially inward side, a radially outward side, and two ends that are respectively spaced apart from the circumferential surface by two bridges, wherein each bridge has thinner and thicker portions that are respectively positioned near the radially inward and outward sides. One or more permanent magnets are inserted in each hole and arranged to transfer centrifugal forces acting on the magnets during operation to portions of the bridges.

Abstract: A rotor includes a cylindrical rotor core having an outer circumferential surface and a plurality of magnet insertion holes formed in the rotor core and arranged circumferentially at a preset angular interval about the rotational axis of the rotor core. Each hole extends in a direction parallel to the rotational axis and has a cross section of a generally elongated slit. The elongated slit is curved concave relative to the circumferential surface and has a radially inward side, a radially outward side, and two ends that are respectively spaced apart from the circumferential surface by two bridges, wherein each bridge has thinner and thicker portions that are respectively positioned near the radially inward and outward sides. One or more permanent magnets are inserted in each hole and arranged to transfer centrifugal forces acting on the magnets during operation to portions of the bridges.

Abstract: A stator of an electrical machine operable as a motor or a generator, applicable to a radial-axial type machine. The stator includes a plurality of stator segments disposed circumferentially about an axis. Each segment has a generally wedge shaped core and a winding wound around the core. The winding is bent to have portions that are disposed on multiple planes. The core includes an elongated wedge tip portions aligned parallel to the axis and an outer radial face opposite to the tip portion. The multiple planes include at least one plane substantially normal to the axis and at least one plane tangential to the radial face.

Abstract: A method for controlling a brushless electric motor including a rotor, a sense element with a plurality of magnetic pole pairs, and first and second sensors mounted less than or equal to 120 electrical degrees apart with sensing planes oriented perpendicular to an adjacent surface of the sense element and perpendicular to a movement direction of the sense element relative to the sensors, wherein one of a) the sense element and b) the first and second sensors is mounted in a fixed relationship with the rotor, the method including measuring magnetic flux of the plurality of magnetic pole pairs using the first and second sensors and outputting a corresponding measurement signal for each at least one first and second sensor, determining a rotational position of the rotor based on the measurement signals, and controlling the motor based on the determined rotor position.

Abstract: An inexpensive and accurate device for sensing rotor position and detecting rotational speed over a broad range of speeds in an electric motor includes a sense ring magnet and two analog Hall effect sensors. The sense ring is magnetized in an alternating north-south fashion with a number of poles that correspond to a number of motor field poles. The Hall effect sensors are placed so that they measure magnetic flux tangential to the sense ring. The Hall effect sensors are preferably located at a distance from the sense ring where the Hall effect sensor output waveforms are substantially triangular, with a highly linear portion centered at zero flux between the minimum and maximum waveform peaks. The linear portions of the waveforms are decoded using an A/D converter and control software to provide an accurate measure of the rotor position.