An independent speed variable frequency alternating current (AC) generator apparatus may include a rotor and a stator, the rotor configured to rotate relative to the stator. The apparatus may further include a magnetic field source attached to the rotor and configured to generate a first rotating magnetic field upon rotation of the rotor, where a rotational frequency of the first rotating magnetic field is dependent on a rotational frequency of the rotor. The apparatus may also include a main rotor winding attached to the rotor and configured to generate a second rotating magnetic field upon the rotation of the rotor, where a rotational frequency of the second rotating magnetic field is independent of the rotational frequency of the rotor.

An independent speed variable frequency alternating current (AC) generator apparatus may include a rotor and a stator, the rotor configured to rotate relative to the stator. The apparatus may further include a magnetic field source attached to the rotor and configured to generate a first rotating magnetic field upon rotation of the rotor, where a rotational frequency of the first rotating magnetic field is dependent on a rotational frequency of the rotor. The apparatus may also include a main rotor winding attached to the rotor and configured to generate a second rotating magnetic field upon the rotation of the rotor, where a rotational frequency of the second rotating magnetic field is independent of the rotational frequency of the rotor.

A three-phase generator for an installation for generating a three-phase alternating voltage, has a two-pole rotor having two magnetic poles, wherein the magnetic poles are arranged irregularly and offset to one another on the periphery with respect to a rotor rotational axis of the rotor

A main field circuit of an electrical generator and associated system and method are disclosed. The main field circuit comprises a main field winding configured to conduct a main field current, and a counter-field winding arranged proximate to the main field winding. The main field circuit further comprises a switch element configured to selectively couple at least a portion of the main field current into the counter-field winding to reduce a magnitude of the main field current. Coupling at least a portion of the main field current into the counter-field winding may be performed responsive to one or predefined conditions, such as a predefined load fault condition and enabling a predefined field weakening operation.

A field winding type rotary machine includes a stator having a stator core and a stator coil wound on the stator core, a rotor having a rotor core and a rotor field coil wound on the rotor core, and a rectifier element connected between both ends of the rotor field coil. The field winding type rotary machine includes a capacitor having a first terminal connected to an anode terminal of the rectifier element and a second terminal connected to any point of the rotor field coil.

A field winding type rotary machine includes a stator having a stator core and a stator coil wound on the stator core, a rotor having a rotor core and a rotor field coil wound on the rotor core, and a rectifier element connected between both ends of the rotor field coil. The field winding type rotary machine includes a capacitor having a first terminal connected to an anode terminal of the rectifier element and a second terminal connected to any point of the rotor field coil.

The current invention relates to a magnetic pole assembly, providing flux to an air gap, comprising one or more magnetic pole pieces and one or more sources of magnetic flux. Said one or more sources of magnetic flux lie adjacent to the axial faces and circumferential faces and one of the radially inner face or radially outer face of each magnetic pole piece. Thereby to allow flux created by said one or more sources of magnetic flux to enter the one or more magnetic pole pieces in order to focus the magnetic flux of said pole piece towards and out of the radial surface not having a source of magnetic flux adjacent thereto. Such an arrangement, increases the flux density in the air gap adjacent to said radial surface not having a source of magnetic flux adjacent thereto.

A stator defines multiple stator poles with associated stator windings. A rotor defines multiple rotor poles with associated rotor windings configured to be energized substantially by the stator. The rotor defines a rotor field energizable by magnetic fields produced by the stator windings to produce relative force between the rotor and the stator. An active rectifier is conductively coupled to one or more first rotor windings. The active rectifier is configured to control a direction of current flow through the one or more first rotor windings responsive to a signal received wirelessly from the stator by one or more second rotor windings.

A stator defines multiple stator poles with associated stator windings. A rotor defines multiple fixed rotor poles with associated teeth with a ferromagnetic material. The fixed rotor poles have associated rotor windings configured to be energized substantially by the stator. Each of the rotor windings is associated with the tooth. Each of the rotor windings includes an alternating current (AC) coil (or auxiliary coil) configured to carry an AC current induced by an AC current flowing in the stator. A direct current (DC) coil (or primary coil) defines a rotor field energizable by magnetic fields produced by the stator windings to produce relative forces between the rotor and the stator. The DC coil is at least partially powered or controlled by the AC coil.

A stator defines multiple stator poles with associated stator windings. A rotor defines multiple fixed rotor poles with associated teeth with a ferromagnetic material. The fixed rotor poles have associated rotor windings configured to be energized substantially by the stator. Each of the rotor windings is associated with the tooth. Each of the rotor windings includes an alternating current (AC) coil (or auxiliary coil) configured to carry an AC current induced by an AC current flowing in the stator. A direct current (DC) coil (or primary coil) defines a rotor field energizable by magnetic fields produced by the stator windings to produce relative forces between the rotor and the stator. The DC coil is at least partially powered or controlled by the AC coil.