Abstract: A rotor 10 for an electrical machine comprising a rotor body 12, at least one magnet 18 coupled to the rotor body 12 and a retainer 22 for retaining the at least one magnet 18 to the rotor body 12, the retainer 22 comprising at least one elongate fibre in a metal matrix.

Abstract: Generators 12a are for a distributed generation system. A control system 32a receives information about network faults 14a. In normal conditions, the control system 32a controls the field current in the field coils of the generator 12a, to maintain generator output voltage at the rated value. At the onset of fault conditions, the control system 32a changes the manner in which field current is controlled, in order to reduce the fault current put onto the network.

Abstract: Use of a common electrical power bus to which a number of electrical power generators and consumers are coupled is well known. Typically, a high electrical capacitance is provided across the bus in order to provide stabilisation in the switching of generators and consumer devices as well as differences in the operational performances of the electrical power generators. Particularly in aerospace applications provision of high capacity electrical capacitors creates problems. By providing a feedback control and an electrical power converter take primary electrical power from an electro-mechanical converter associated with a rotating component of a prime mover, electrical power stabilisation is achieved by applying torque changes through the electromechanical converter to the rotating component of the prime mover such that stored electrical power can then be drawn as required to accommodate transients in electrical power on the bus.

Abstract: A component of an electric machine 46, the component comprising a core 10; two or more teeth 14 extending radially therefrom; at least one electromagnetic winding 12, each winding 12 around at least one of the teeth 14; wherein the core 10 having a cooling arrangement including at least one cooling insert 48 located between adjacent windings 12 and whereby in use a cooling fluid being arranged to flow through the at least one cooling insert 48 to facilitate heat transfer and dissipation from the electromagnetic windings 12. The cooling inserts providing improved cooling, structural support to the windings, and electrical insulation between the windings and the core.

Abstract: In order to be acceptable for safety critical applications, it is necessary for an electrical machine to allow continued operation despite an electrical short circuit in one of the operational phases of that electrical machine. It will be appreciated that an electrical short circuit creates excessive electrical current through the short circuit with significant heating and other detrimental effects. However, the electrical machine can operate with one operational phase disabled. In such circumstances, the present invention incorporates means for determining an electrical short circuit has occurred and then injects an electrical current approximately equal to or greater than the rated electrical current. In such circumstances, the operational phase or coil 4, 24, 34 is effectively protected despite the electrical short circuit and hence the electrical machine can continue to operate.

Abstract: Generators 12a are for a distributed generation system. A control system 32a receives information about network faults 14a. In normal conditions, the control system 32a controls the field current in the field coils of the generator 12a, to maintain generator output voltage at the rated value. At the onset of fault conditions, the control system 32a changes the manner in which field current is controlled, in order to reduce the fault current put onto the network.

Abstract: An electrical conductor winding (70) comprises a plurality of laminates of electrical insulation (72). Each laminate of electrical insulation (72) has a slot (78) on one surface (76). Each laminate of electrical insulation (70) has an electrical conductor (82) arranged in the slot (78). An electrical connector (84) connects the electrical conductor (82) in one laminate of electrical insulation (78) with the electrical conductor (82) in an adjacent laminate of electrical insulation (72). The laminates of electrical insulation (72) are arranged such that the surface (74) of one laminate of electrical insulation (72) abuts and is bonded to the surface (76) of an adjacent laminate of electrical insulation (12). The laminates of electrical insulation (12) comprise a glass-ceramic material. The electrical conductor windings allow active magnetic bearings, electric motors and electric generators to be used at temperatures up to 500° C. for example in gas turbine engines.

Abstract: A switched reluctance electrical machine comprising a rotor 2 and coils 4 is arranged to provide constant power or torque output over a wider range of operational speeds. The coils 4 each include a tap T or a number of taps in order to allow the effective number of turns in each coil 4 to be altered dependent upon rotor 2 speed.

Abstract: An electrical machine comprises a combined magnetic gearbox and electrical generator. A first set of permanent magnets (30) are arranged on a rotor (16) to produce a spatially variable first magnetic field. A second set of permanent magnets (32) are arranged on a rotor (40,41,43), stationary pole pieces (36) are positioned between the first set of permanent magnets (30) and the second set of permanent magnets (32) to interfere with the first magnetic field. Rotation of the rotor (16) relative to the pole pieces (36) produces a second magnetic field which rotates the second set of permanent magnets (32). A stator (42) has windings (46) to transduce a changing second magnetic field produced by the rotation of the second set of permanent magnets (32) into an electrical voltage. The electrical machine is useful for a wind turbine generator. Alternatively the arrangement may be modified to produce an electrical motor.

Abstract: An inner rotatable shaft 16 is located within an outer rotatable shaft 18. A stator 52 is provided around the shaft 18. The shaft 18 has a circumferential ring of regions 54a, 54b alternately of relatively high and relatively low magnetic permeability. Flux is therefore transmitted between the stator 52 and the shaft 16 through the regions 54, preferentially through the high permeability regions 54a. Commutation of the stator windings, preferably in synchrony with the speed of rotation of the shaft 18, allows the stator 52 and shaft 16 to interact in the form of an active magnetic bearing. The affect of the presence of the shaft 18 on this interaction is significantly reduced or eliminated.

Abstract: An electrical machine comprises a combined magnetic gearbox and electrical generator. A first set of permanent magnets (30) are arranged on a rotor (16) to produce a spatially variable first magnetic field. A second set of permanent magnets (32) are arranged on a rotor (40, 41, 43), stationary pole pieces (36) are positioned between the first set of permanent magnets (30) and the second set of permanent magnets (32) to interfere with the first magnetic field. Rotation of the rotor (16) relative to the pole pieces (36) produces a second magnetic field which rotates the second set of permanent magnets (32). A stator (42) has windings (46) to transduce a changing second magnetic field produced by the rotation of the second set of permanent magnets (32) into an electrical voltage. The electrical machine is useful for a wind turbine generator. Alternatively the arrangement may be modified to produce an electrical motor.

Abstract: An electrical conductor winding (70) comprises a plurality of laminates of electrical insulation (72). Each laminate of electrical insulation (72) has a slot (78) on one surface (76). Each laminate of electrical insulation (70) has an electrical conductor (82) arranged in the slot (78). An electrical connector (84) connects the electrical conductor (82) in one laminate of electrical insulation (78) with the electrical conductor (82) in an adjacent laminate of electrical insulation (72). The laminates of electrical insulation (72) are arranged such that the surface (74) of one laminate of electrical insulation (72) abuts and is bonded to the surface (76) of an adjacent laminate of electrical insulation (12). The laminates of electrical insulation (12) comprise a glass-ceramic material. The electrical conductor windings allow active magnetic bearings, electric motors and electric generators to be used at temperatures up to 500° C. for example in gas turbine engines.

Abstract: An electrical conductor winding (70) comprises a plurality of laminates of electrical insulation (72). Each laminate of electrical insulation (72) has a slot (78) on one surface (76). Each laminate of electrical insulation (70) has an electrical conductor (82) arranged in the slot (78). An electrical connector (84) connects the electrical conductor (82) in one laminate of electrical insulation (78) with the electrical conductor (82) in an adjacent laminate of electrical insulation (72). The laminates of electrical insulation (72) are arranged such that the surface (74) of one laminate of electrical insulation (72) abuts and is bonded to the surface (76) of an adjacent laminate of electrical insulation (12). The laminates of electrical insulation (12) comprise a glass-ceramic material. The electrical conductor windings allow active magnetic bearings, electric motors and electric generators to be used at temperatures up to 500° C. for example in gas turbine engines.

Abstract: An inner rotatable shaft 16 is located within an outer rotatable shaft 18. A stator 52 is provided around the shaft 18. The shaft 18 has a circumferential ring of regions 54a,54b alternately of relatively high and relatively low magnetic permeability. Flux is therefore transmitted between the stator 52 and the shaft 16 through the regions 54, preferentially through the high permeability regions 54a. Commutation of the stator windings, preferably in synchrony with the speed of rotation of the shaft 18, allows the stator 52 and shaft 16 to interact in the form of an active magnetic bearing. The affect of the presence of the shaft 18 on this interaction is significantly reduced or eliminated.

Abstract: An electrical conductor winding (70) comprises a plurality of laminates of electrical insulation (72). Each laminate of electrical insulation (72) has a slot (78) on one surface (76). Each laminate of electrical insulation (70) has an electrical conductor (82) arranged in the slot (78). An electrical connector (84) connects the electrical conductor (82) in one laminate of electrical insulation (78) with the electrical conductor (82) in an adjacent laminate of electrical insulation (72). The laminates of electrical insulation (72) are arranged such that the surface (74) of one laminate of electrical insulation (72) abuts and is bonded to the surface (76) of an adjacent laminate of electrical insulation (12). The laminates of electrical insulation (12) comprise a glass-ceramic material. The electrical conductor windings allow active magnetic bearings, electric motors and electric generators to be used at temperatures up to 500° C. for example in gas turbine engines.