Abstract: A turbocharger comprises a turbine wheel and a compressor wheel mounted to a turbocharger shaft. An electric induction motor is provided for assisting rotation of the compressor wheel in predetermined circumstances. The motor comprises a fixed stator having motor field coils which generate a rotating magnetic field when energised by an AC control signal which induces eddy current flow in a rotor to generate a rotor magnetic field which in turn interacts with the stator magnetic field producing torque in the rotor.

Abstract: The present invention provides an open centred hydroelectric turbine having an annular stator and a rotor mounted for rotation within the stator, the turbine comprising a magnetic bearing which is adapted, by having opposing sets of rotor and stator magnets which are offset at a top and bottom of the stator, to provide both axial and radial support to the rotor.

Abstract: A rotor for an electrical generator and a generator incorporating such a rotor, the rotor consisting of a central hub, a radially spaced concentric rim portion with rotor magnetic elements mounted upon it, and a plurality of elongate tension members extending generally between the hub and the rim, maintained substantially in tension so as to maintain the rim substantially in compression. The hub is rotatably driven by an axially spaced power drive means such as a wind or marine current turbine.

Abstract: A turbocharger comprises a turbine wheel and a compressor wheel mounted to a turbocharger shaft. An electric induction motor is provided for assisting rotation of the compressor wheel in predetermined circumstances. The motor comprises a fixed stator having motor field coils which generate a rotating magnetic field when energised by an AC control signal which induces eddy current flow in a rotor to generate a rotor magnetic field which in turn interacts with the stator magnetic field producing torque in the rotor.

Abstract: A turbocharger comprises a turbine wheel and a compressor wheel mounted to a turbocharger shaft. An electric induction motor is provided for assisting rotation of the compressor wheel in predetermined circumstances. The motor comprises a fixed stator having motor field coils which generate a rotating magnetic field when energised by an AC control signal which induces eddy current flow in a rotor to generate a rotor magnetic field which in turn interacts with the stator magnetic field producing torque in the rotor.

Abstract: A turbocharger comprises a turbine wheel and a compressor wheel mounted to a turbocharger shaft. An electric induction motor is provided for assisting rotation of the compressor wheel in predetermined circumstances. The motor comprises a fixed stator having motor field coils which generate a rotating magnetic field when energised by an AC control signal which induces eddy current flow in a rotor to generate a rotor magnetic field which in turn interacts with the stator magnetic field producing torque in the rotor.

Abstract: A rotor for an electrical generator and a generator incorporating such a rotor, the rotor consisting of a central hub, a radially spaced concentric rim portion with rotor magnetic elements mounted upon it, and a plurality of elongate tension members extending generally between the hub and the rim, maintained substantially in tension so as to maintain the rim substantially in compression. The hub is rotatably driven by an axially spaced power drive means such as a wind or marine current turbine.

Abstract: A surge protection device has a modular construction so that a manufacturer can assemble the parts in any combination desired by a customer. This eliminates any need to maintain large varieties of surge protection modules in inventory. The modular construction includes a housing having a plurality of bores formed therein into which is press fit long pins and short pins for electrical communication with an external power source and an internal customer telephone circuit, respectively. The housing further includes a pair of recesses into each of which may be press fit a positive temperature coefficient resistor. A first embodiment of spring clips helps hold the positive coefficient resistors in place and provides needed electrical contacts, and a second embodiment of spring clips further includes an elongate part that extends to a test point opening formed in a cover for the modular device.

Abstract: A generator or a 3-phase motor is arranged to provide multipolar permanent magnet excitation in combination with multipolar reluctance distribution wherein different numbers of poles are used for the permanent magnet excitation and for the reluctance distribution so that the principal working flux has a finite waveform. An annular rotor rotates about a cruciform stator. The magnets are buried in pole pieces of the stator so they converge radially inwardly with a triangular pole piece between them. Each pole piece is joined to the remainder of the stator by a bridge piece. The inner periphery of the rotor is formed as a circumferential array of teeth separated by recesses. The rotor may be within an annular stator or the machine may be linear.

Abstract: An electromagnetic machine which is suitable for use as a direct-drive, directly-coupled, mains electricity generator (14) to be driven by a low speed device such as a wind turbine (18), consists of one or more rotor rings (30) of many permanent magnets (40) of alternating polarity, with coaxial stator rings (28) of many laminated yokes (35), each yoke defining slots to locate coils (38). The yokes (35) and coils (38) form modules which are supported by beams (32) relative to the rotor rings (30). The rotor rings (30) may also be of modular construction. Manufacture and assembly are thereby simplified, and sub-harmonic magnetic flux components are suppressed.