An axial flow turbine for generating electricity in low-head environments comprises a runner supported by guide vanes that are curved or contoured to direct flowing water onto fixed turbine blades. The axial flow turbine has a housing that provides an outer draft tube. A second inner draft tube is supported within the outer draft. The axial flow turbine may have a bulb or pit-type housing at the intake chamber for housing a direct-drive variable-speed permanent magnet synchronous generator (PMSG) and power converter system. The axial flow turbine may be installed as a single modular unit in low head environments.

The invention relates to a support structure (17) for a laminated core (9) of a stator segment (13) of a dynamoelectric machine having an external rotor, the support structure (17) having two joint plates (6) and two curved pressure plates (1), the respective longitudinal faces of which are in each case mutually opposed, and which encompass a predefinable space and can be connected at their abutting edges. The support structure also has substantially radial bars or ribs (3) between the pressure plates (1) and at least one element having polygonal cut-outs, which element is connected to a longitudinal face of the ribs (3) and forms a base plate of the support structure (17).

Electrical machines as provided herein can include a shaftless rotor with an annular array of permanent magnets; and a stator with an annular ferromagnetic core and a plurality of electromagnetic inductors about the ferromagnetic core. The stator is located adjacent to and substantially co-axial with the shaftless rotor; and a fluid thrust bearing located in an axially planar gap between the stator and the shaftless rotor. The annular array of the permanent magnets of the shaftless rotor and the annular ferromagnetic core and electromagnetic inductors of the stator have a magnetic attraction that provides a co-axially centering force on the shaftless rotor.

An apparatus for generating energy from ocean waves, the apparatus including a first or outer section arranged to be coupled to a sea floor and a second or inner section that is at least partially received by and slidably moveable within the first section. The first section includes a float housing arranged to be located toward or at a sea surface and an armature housing extending from the float housing toward the sea floor, the float housing having one or more apertures so that a water level within the float housing is substantially similar to or follows that of the sea surface. The second section includes a float slidably received by the float housing and a stem carrying a magnetic element that extends from the float so as to be receivable by the armature housing. The arrangement is such that the float travels in substantially vertical direction within the float housing in response to movement of the sea surface thereby the armature housing being moved relative to the magnetic element to generate energy.

A rotor assembly for a motor includes a rotor shaft having a journal portion formed in an axial direction and having a predetermined radius about an axis, and a center shaft portion extending along the axial direction from the journal portion and having a radius smaller than a radius of the journal portion about the axis; a cylindrical, integral permanent magnet inserted into the center shaft portion to surround an outer circumferential surface of the center shaft portion and being supported by the journal portion; and a sleeve inserted into the rotor shaft to surround an outer circumferential surface of the journal portion and an outer circumferential surface of the integral permanent magnet, supporting the integral permanent magnet in the axial direction, and supporting the outer circumferential surface of the center shaft portion in the radial direction.

A wind power generating device includes a stand, a shaft mounted on the stand, a rotor rotatably mounted on the shaft, a stator mounted on the stand and disposed in the rotor, and an impeller mounted on the rotor. The stator includes a plurality of magnetic coil columns and has a central position provided with a hole. The rotor surrounds and covers the stator. The rotor has a central position provided with a bearing mounted on the shaft and has an inner periphery provided with a plurality of magnetic elements corresponding to the magnetic coil columns of the stator. The shaft extends through the hole of the stator and the bearing of the rotor. The bearing of the rotor is locked onto the shaft.

A system and method for harnessing the kinetic energy of the ocean to generate electricity. The system includes a dock made from a buoyant material. The dock has floats at its corners that can receive fixed pillars, such that the floats can move up and down relative to the pillars. Either of the float and the respective pillar has one or more permanent magnets while the other has the conductive coil. The movement of the dock and thus the floats relative to the fixed upstanding pillars results in the generation of electricity.

An hydroelectric unit extends along a longitudinal axis and includes a least one rim-driven hydraulic machine comprising an impeller provided with at least two blades, and at least one motor/generator configured to selectively supply mechanical energy to the impeller or convert mechanical energy produced by the impeller into electricity. The motor/generator includes an annular rotor arranged about the impeller and an annular stator arranged, at a distance, about the annular rotor; the annular rotor being coupled to the impeller and including a plurality of rotor poles, which are distributed along an annular surface, are arranged parallel one to another and extend transversal to a plane containing the longitudinal axis forming a first angle with the plane containing the longitudinal axis. The annular stator includes a plurality of stator windings and a plurality of stator slots configured to guide the magnetic flux and to house respective stator windings. The stator slots are arranged parallel one to another and extend transversal to a plane containing the longitudinal axis forming a second angle with the plane containing the longitudinal axis.

A rotor for a vertical axis wind turbine generator features a flywheel having first and second faces located opposite one another across a thickness of the flywheel, and a circumferential perimeter edge joining the first and second faces together around the central axis at a perimeter of the flywheel. A series of cavities are spaced radially inward from the circumferential perimeter edge and open into the flywheel from the first face on a path disposed circumferentially about the central axis. A series of permanent magnets carried in the cavities have the opposing poles of adjacent magnets facing in the same axial direction. The recessed magnet configuration avoids the separate magnet-retention means required for flush-mount configurations, and increases the performance of the generator.

Substantially horizontal axis water turbine assemblies for generating electrical power in areas having poor sources of water flow including rotors mounted within housings in such a manner so as to minimize water resistance to the rotor blades with rotor blades passing through upper rotor return air spaces created within the housings and wherein the turbine assemblies may be mounted within support structures that both channel water flow to the turbine assemblies and facilitate access to the components thereof.