An end structure for a rotor of an electric machine is attachable to an end of the rotor. The end structure includes a ring arrangement, a rotational axis of which is parallel to that of the stacked rotor, and at least one reinforcing structure at least partly within the ring arrangement. A value of a tensile strength of the at least one reinforcing structure is higher than that of the ring arrangement.

An end structure for a rotor of an electric machine is attachable to an end of the rotor. The end structure includes a ring arrangement, a rotational axis of which is parallel to that of the stacked rotor, and at least one reinforcing structure at least partly within the ring arrangement. A value of a tensile strength of the at least one reinforcing structure is higher than that of the ring arrangement.

A rotor designed as a reluctance rotor includes a laminated core which defines an axis and has end faces. The laminated core includes sheets which are at least partly axially layered, with the sheets having flux-conducting portions and flux-blocking portions to form a specified number of poles. A cage made of electric conductors runs in a substantially axial direction and is connected at the end faces of the laminated core by short-circuit rings. The conductors are located in a radially outer region of at least some of the flux-blocking portions arranged one behind another substantially in the axial direction, with the conductors defining conductor bars formed by conductive material at a quantity determinative to define an internal diameter of the conductor bars.

A rotor designed as a reluctance rotor includes a laminated core which defines an axis and has end faces. The laminated core includes sheets which are at least partly axially layered, with the sheets having flux-conducting portions and flux-blocking portions to form a specified number of poles. A cage made of electric conductors runs in a substantially axial direction and is connected at the end faces of the laminated core by short-circuit rings. The conductors are located in a radially outer region of at least some of the flux-blocking portions arranged one behind another substantially in the axial direction, with the conductors defining conductor bars formed by conductive material at a quantity determinative to define an internal diameter of the conductor bars.

A rotor for a reluctance machine and a method of producing a rotor for a reluctance machine is provided. The rotor is formed as a soft magnetic element which is cylindrical in shape. The soft magnetic element has recesses for forming flux barriers, one or more flux barriers being at least partially filled with a filler material, and the filler material of said flux barriers extending up to the rotor periphery and forming part of the rotor periphery.

A rotor for a reluctance machine and a method of producing a rotor for a reluctance machine is provided. The rotor is formed as a soft magnetic element which is cylindrical in shape. The soft magnetic element has recesses for forming flux barriers, one or more flux barriers being at least partially filled with a filler material, and the filler material of said flux barriers extending up to the rotor periphery and forming part of the rotor periphery.

A motor driving method is applied to a motor with a rotor comprising a magnetic reluctance structure. The motor driving method comprises enabling the motor by an asynchronous driving method, controlling the motor by the asynchronous driving method according to a speed regulation command, detecting a rotor speed of the motor and determining whether the rotor speed is larger than a speed threshold, and when the rotor speed is larger than the speed threshold, controlling the motor by a synchronous driving method.

A synchronous reluctance type rotary electric machine of an embodiment includes a shaft and a rotor core. The shaft rotates around a rotation axis. The rotor core is fixed to the shaft and includes multi-layered hollow parts having a convex shape toward a radially inward side formed for each pole in cross section. Then, when a center in a circumferential direction of one pole is a pole center, a hollow part closest to the shaft among the plurality of hollow parts is a first hollow part, a hollow part positioned next to the first hollow part is a second hollow part, and a hollow part positioned on a side opposite to the first hollow part with respect to the second hollow part is a third hollow part, a width W1 between the first hollow part and the second hollow part on the pole center and a width W2 between the second hollow part and the third hollow part on the pole center are set to satisfy W1W2.

A synchronous reluctance type rotary electric machine of an embodiment includes a shaft and a rotor core. The shaft rotates around a rotation axis. The rotor core is fixed to the shaft and includes multi-layered hollow parts having a convex shape toward a radially inward side formed for each pole in cross section. Then, when a center in a circumferential direction of one pole is a pole center, a hollow part closest to the shaft among the plurality of hollow parts is a first hollow part, a hollow part positioned next to the first hollow part is a second hollow part, and a hollow part positioned on a side opposite to the first hollow part with respect to the second hollow part is a third hollow part, a width W1 between the first hollow part and the second hollow part on the pole center and a width W2 between the second hollow part and the third hollow part on the pole center are set to satisfy W1W2.

A field discharge resistor unit according to an embodiment of the present invention is a device coupled to a rotary shaft of a synchronous motor and connected to a coil wound on a rotor of the synchronous motor, to reduce a magnitude of an electric current flowing through the coil wound on the rotor, and comprises: a hub which has a receiving space therein and is coupled to the rotary shaft of the synchronous motor so that a rotary movement of the hub matches that of the shaft; and at least one conductor disk received in the receiving space of the hub and may function as a resistor when an electric current flows therethrough.