A high-frequency rotary transformer, a machine and a high frequency transformer are defined that are simpler to manufacture and less expensive than existing transformers and machines. The high-frequency rotary transformer includes: a primary transformer core comprising a plurality of primary core elements, each defining a primary transformer winding portion; a secondary transformer core comprising a plurality of secondary core elements, each defining a secondary transformer winding portion; a primary winding associated with each of the primary core elements; and a secondary winding associated with each of the secondary core elements. The primary transformer core and the secondary transformer core together define a transformer core having a flux pathway linking the primary and secondary windings, and the primary transformer core and the secondary transformer core are configured to rotate relative to each other. A magnetic flux concentrator may be used to direct magnetic flux towards an inside of the rotary transformer.

A rotary transformer for an electrical machine includes a rotary printed circuit board and a stator printed circuit board. The rotary printed circuit board is operatively connected to the stator printed circuit board for relative rotation with respect to the stator printed circuit board. A conductor is fixed to the one of the printed circuit boards and includes a spiral coil for transferring electrical energy between the rotary printed circuit board and stator printed circuit board.

A rotary transformer for an electrical machine includes a rotary printed circuit board and a stator printed circuit board. The rotary printed circuit board is operatively connected to the stator printed circuit board for relative rotation with respect to the stator printed circuit board. A conductor is fixed to the one of the printed circuit boards and includes a spiral coil for transferring electrical energy between the rotary printed circuit board and stator printed circuit board.

An electrical machine with a rotor or the stator including a plurality of discrete field modules, and the other one of the rotor and the stator including a plurality of armature coils connected to different power converters. Each field module includes one or more field coils which can be activated independent of the field coils of the neighbouring field modules. When at least one of the field coils is inactivated, e.g. because of a defect, each of the power converters is allowing less power to pass through when an armature coil connected to it is moving over an inactivated field coil, and more power to pass through when the armature coil connected to it is moving over an activated field coil.

An electrical machine with a rotor or the stator including a plurality of discrete field modules, and the other one of the rotor and the stator including a plurality of armature coils connected to different power converters. Each field module includes one or more field coils which can be activated independent of the field coils of the neighbouring field modules. When at least one of the field coils is inactivated, e.g. because of a defect, each of the power converters is allowing less power to pass through when an armature coil connected to it is moving over an inactivated field coil, and more power to pass through when the armature coil connected to it is moving over an activated field coil.

In one embodiment, a generator includes an alternating current exciter to output first, second and third alternating currents respectively having first, second and third phases, and a rotary rectifier to convert the first, second and third alternating currents into first, second and third direct currents, respectively. The generator further includes a rotating shaft on which the exciter and the rectifier are mounted, and plural conductors mounted on the shaft, and including one or more first conductors, one or more second conductors and one or more third conductors to respectively supply the first, second and third alternating currents from the exciter to the rectifier. The plural conductors include one or more conductor groups in each of which two or more conductors are collectively arranged, and each of the conductor groups includes the two or more conductors arranged to cancel a magnetic field around each conductor in the same group.

In one embodiment, a generator includes an alternating current exciter to output first, second and third alternating currents respectively having first, second and third phases, and a rotary rectifier to convert the first, second and third alternating currents into first, second and third direct currents, respectively. The generator further includes a rotating shaft on which the exciter and the rectifier are mounted, and plural conductors mounted on the shaft, and including one or more first conductors, one or more second conductors and one or more third conductors to respectively supply the first, second and third alternating currents from the exciter to the rectifier. The plural conductors include one or more conductor groups in each of which two or more conductors are collectively arranged, and each of the conductor groups includes the two or more conductors arranged to cancel a magnetic field around each conductor in the same group.

In a rotating electric machine, a stator includes a stator winding, a field winding includes a series-connection body including a plurality of winding portions, and a rotor includes main pole portions protruding from a rotor core in a radial direction. A harmonic current for inducing a field current in the field winding flows to the stator winding. A rectifying element is connected in series to the field winding, configures a closed circuit with the field winding, and rectifies the field current that flows to the field winding to flow in one direction. In a capacitor, a first end is connected to a connection point between adjacent winding portions and a second end is connected to either of both ends of the rectifying element. A partitioning portion is disposed between at least a single set of adjacent winding portions among the plurality of winding portions and includes a magnetic material.

An electromagnetic induction power generator includes: a current transformer attached to a power transmission line; a rectifier circuit for rectifying an AC voltage output from the current transformer; and a regulator circuit for regulating a DC voltage output from the rectifier circuit. The current transformer has a magnetic core attached to the power transmission line serving as a primary winding and a secondary winding magnetically coupled to the power transmission line through the magnetic core. The magnetic core is configured to start to be magnetically saturated around the minimum value within the fluctuation range of a current flowing through the power transmission line.

An electromagnetic induction power generator includes: a current transformer attached to a power transmission line; a rectifier circuit for rectifying an AC voltage output from the current transformer; and a regulator circuit for regulating a DC voltage output from the rectifier circuit. The current transformer has a magnetic core attached to the power transmission line serving as a primary winding and a secondary winding magnetically coupled to the power transmission line through the magnetic core. The magnetic core is configured to start to be magnetically saturated around the minimum value within the fluctuation range of a current flowing through the power transmission line.