Systems, methods, and apparatus for secondary windings to modify a permanent magnet (PM) field of a permanent magnet synchronous generator (PMSG) are disclosed. In one or more embodiments, a disclosed system for a PMSG comprises a permanent magnet (PM) of the PMSG to rotate and to generate a permanent magnet field. The system further comprises a plurality of stator primary windings (SPW), of the PMSG, to generate primary currents from the permanent magnet field. Further, the system comprises a plurality of stator secondary windings (SSW), of the PMSG, to draw secondary currents from a power source, and to generate a stator secondary winding magnetic field from the secondary currents. In one or more embodiments, the permanent magnet field and the stator secondary winding magnetic field together create an overall magnetic field for the PMSG.

Systems, methods, and apparatus for secondary windings to modify a permanent magnet (PM) field of a permanent magnet synchronous generator (PMSG) are disclosed. In one or more embodiments, a disclosed system for a PMSG comprises a permanent magnet (PM) of the PMSG to rotate and to generate a permanent magnet field. The system further comprises a plurality of stator primary windings (SPW), of the PMSG, to generate primary currents from the permanent magnet field. Further, the system comprises a plurality of stator secondary windings (SSW), of the PMSG, to draw secondary currents from a power source, and to generate a stator secondary winding magnetic field from the secondary currents. In one or more embodiments, the permanent magnet field and the stator secondary winding magnetic field together create an overall magnetic field for the PMSG.

An electric motor is disclosed that includes a stator winding defining a plurality of poles, with the winding being controllable to switch between a first number of poles and a second number of poles. A rotor rotatable within the stator includes a first group of magnetic flux barriers being without permanent magnet material and a second group of magnetic flux barriers at least partially filled with a permanent magnet material. A method of operating a line-start electric motor is also disclosed.

An electric motor is disclosed that includes a stator winding defining a plurality of poles, with the winding being controllable to switch between a first number of poles and a second number of poles. A rotor rotatable within the stator includes a first group of magnetic flux barriers being without permanent magnet material and a second group of magnetic flux barriers at least partially filled with a permanent magnet material. A method of operating a line-start electric motor is also disclosed.

A method of manufacturing a rotor of an electric motor or an electric generator includes positioning a plurality of amortisseur bars and using additive manufacturing to place electrically conductive material. More specifically, positioning the amortisseur bars may include circumferentially positioning the bars around a rotor stack and using additive manufacturing to place electrically conductive material may include forming a non-solid pattern of electrically conductive material, such as a pattern of electrically conductive traces, across opposite axial ends of the rotor stack to electrically interconnect an amortisseur circuit.

A rotor includes a rotor core formed by laminating steel sheets, first and second plate members respectively arranged on first and second axial sides of the rotor core, first short-circuiting pins held by the first plate member and having been inserted in respective pin-receiving holes of the rotor core from the first axial side, and second short-circuiting pins held by the second plate member and having been inserted in respective pin-receiving holes of the rotor core from the second axial side. One of the first short-circuiting pins and one of the second short-circuiting pins respectively function as first and second positioning pins. For at least one of first and second positioning pin-receiving holes in which the first and second positioning pins are respectively received, each of the steel sheets forming the rotor core has a chamfered or curved corner around the positioning pin-receiving hole on a positioning pin insertion side.

A rotor includes a rotor core formed by laminating steel sheets, first and second plate members respectively arranged on first and second axial sides of the rotor core, first short-circuiting pins held by the first plate member and having been inserted in respective pin-receiving holes of the rotor core from the first axial side, and second short-circuiting pins held by the second plate member and having been inserted in respective pin-receiving holes of the rotor core from the second axial side. One of the first short-circuiting pins and one of the second short-circuiting pins respectively function as first and second positioning pins. For at least one of first and second positioning pin-receiving holes in which the first and second positioning pins are respectively received, each of the steel sheets forming the rotor core has a chamfered or curved corner around the positioning pin-receiving hole on a positioning pin insertion side.

The disclosed embodiments describe a partially caged rotor for use in an interior permanent magnet motor and techniques for fabricating thereof. In some embodiments, a caged rotor includes: a rotor core having a shaft; a rotor cage comprising a plurality of conductor bars; and a plurality of permanent magnets at least partially disposed inside a plurality of mounting holes of the core, the plurality of permanent magnets and the plurality of mounting holes forming a plurality of cavities inside the core; wherein each conductor bar is disposed at a respective cavity of the plurality of cavities such that the plurality of conductor bars is of a number greater or equal to 8 and less or equal to 64.

A resistance module for increasing a runup torque for a rotor of an electric machine with a rotor winding includes first and second connection points, a plurality of electrically-conductive layers electrically connected to the first and second connection points. Each of the layers surrounds an axis of the resistance module at least partially in a circumferential direction and has a layer start point and a layer end point. At least one of the layers is configured in an undulating shape in the circumferential direction, with undulations projecting radially outwards. A first insulating layer is disposed between neighboring ones of the layers. The layer end point of one of the layers is electrically connected at a tie point to the layer start point of a neighboring one of the layers. At least one fastening element is disposed between two neighboring undulations in the circumferential direction and radially outside of the layers.

A resistance module for increasing a runup torque for a rotor of an electric machine with a rotor winding includes first and second connection points, a plurality of electrically-conductive layers electrically connected to the first and second connection points. Each of the layers surrounds an axis of the resistance module at least partially in a circumferential direction and has a layer start point and a layer end point. At least one of the layers is configured in an undulating shape in the circumferential direction, with undulations projecting radially outwards. A first insulating layer is disposed between neighboring ones of the layers. The layer end point of one of the layers is electrically connected at a tie point to the layer start point of a neighboring one of the layers. At least one fastening element is disposed between two neighboring undulations in the circumferential direction and radially outside of the layers.