Abstract: A mechanical assembly such as a torque transfer strut for a rotating superconducting machine. The torque transfer strut includes a composite tube having a first end received in a clamping fitting, which may include an end housing or lug, a clamping wedge screwed onto a threaded end housing, and an annular clamping member applying a radial clamping force to the first end of the composite tube at ambient temperature. When cooled, shrinkage of the end housing in the axial direction causes the annular clamping member to maintain or increase radial clamping force, causing the clamping wedge to apply increasing radial force to an inner member deflecting outwardly a plurality of axial fingers. The first end of the composite tube remains clamped between the inner member and an outer member, together defining an annular channel receiving the first end of the composite tube.

Abstract: A circuit breaker comprising a first dc line electrically connectable to first incoming and first outgoing dc lines, wherein the first dc line comprises a first fault-interrupting switch contact system and a first switching aid network. The first switching aid network comprises first and second rectifier strings, wherein each rectifier string comprises one or more series connected reverse blocking power electronic devices that define a first H-bridge rectifier. The first switching aid network further comprises a snubber string, the snubber string comprising at least one series connected power electronic devices capable of being turned on by gate control and a capacitor. The first switching aid network further comprises a pre-charge string comprising at least one series connected power electronic devices capable of being turned on by gate control and a resistor, and a surge arrester connected between the first and second dc output terminals of the first H-bridge rectifier.

Abstract: A command procedure for an active magnetic bearing, the magnetic bearing comprising a series of electromagnetic actuators forming a stator, each actuator being suitable for exerting radial force on the rotor, a ferromagnetic body forming a rotor, kept free of contact between the electromagnetic actuators and suitable for being set in rotation around an axis of rotation, the rotor being suitable to undergo precession movements in particular. Sensors suitable for detecting radial displacements of the rotor and issuing position signals representative of the radial position of the rotor in relation to the actuators. Calculation of at least one actuator command signal the calculation of the command signal consisting of the application of at least one transfer function to the position signals, the transfer function containing a number of correction coefficients.

Abstract: A power distribution system such as a marine power distribution and propulsion system. The system includes an ac busbar and a plurality of active front end power converters. Each AFE power converter includes a first active rectifier/inverter connected to the busbar and a second active rectifier/inverter connected to an electrical load such as an electric propulsion motor. Power sources are connected to the dc link of the AFE power converters and can be operated under the control of a power management controller or power management system.

Abstract: A magnetic core extends in a longitudinal direction and contains at least one stacking of sheets consisting of magnetic material and stacked in a direction of stacking perpendicular to the longitudinal direction, at least one plate of heat-conducting material, presenting first and second opposing faces, and at least one cooling tube positioned in contact with the said first face of the plate in which a heat-bearing fluid is designed to circulate. The plate extends in a plane parallel to the longitudinal direction and to the direction of stacking, its second face being positioned in thermal contact with the sheets in the stacking.

Abstract: A dc electrical machine with a large number of phases. The machine includes a rotor and a stator assembly. The rotor has Np rotating field poles. The stator has Ns winding slots, where Ns/Np is a non-integer ratio. A stator winding includes a plurality of coils received in the winding slots and defines a plurality of stator phases. A power electronic switching assembly includes first and second dc load terminals that can be connected to external equipment and a plurality of switching modules. Each switching module includes power electronic devices and is connected to a respective stator coil. A first proportion of the switching modules are connected together in series between the first and second dc load terminals and a second proportion of the switching modules are connected together in series between the first and second dc load terminals to define two parallel dc circuits.

Abstract: Insulation for a cryogenic component is described. The insulation includes an inner portion formed of a multi-layer insulating material comprising alternating layers of metalized polymer film and polymer netting. An outer supporting mesh surrounds the inner portion and is formed of stainless steel. The insulation is particularly suitable for insulating cryogenic components that move during operation since the supporting mesh acts to support the inner portion against damage caused by forces resulting from motion of the cryogenic component.

Abstract: A rotary drum apparatus comprising a drum rotatable around a longitudinal axis, and at least one electric motor for driving the drum in rotation around the longitudinal axis, each drive motor comprising a stator and a rotor, the rotor comprising at least one ring portion joint together with the drum and extending substantially perpendicularly to the longitudinal axis. The stator of each drive motor extending against a part of circumference of the drum perpendicularly to the longitudinal axis.

Abstract: A semi-conductor electronic device for mounting in a pressed stack assembly. The device comprises a box comprising a lower plate, an upper plate and a lateral wall mechanically connecting the lower plate to the upper plate, the lower and upper plates being electrically conductive, several semi-conductor components, each component comprising a first electrode and a second electrode, the first electrodes being electrically connected to the lower plate and the second electrodes being electrically connected to the upper plate, and elastic parts positioned between the components and a supporting plate chosen from the lower plate and the upper plate.

Abstract: A converter control arrangement (18) for regulating the output current of a dc source power converter (16) comprises a current regulator (20) for regulating the output current based on a comparison of an output current value (Iout) of the dc source power converter (16) with a desired target current value (Itgt). When the output voltage value (Vout) of the dc source power converter (16) is within a normal operating voltage range between minimum and maximum voltage values (Vmin, Vmax) defined with respect to a voltage reference value (Vref) of the dc source power converter (16), the converter control arrangement (18) controls the target current value (Itgt) so that it is equal to a desired reference current value (Iref).

Abstract: A semiconductor device or power electronic device is described. The device includes a pair of pole pieces, each having a profiled surface. A semiconductor body or wafer, preferably of wide bandgap electronic material, is located between the pole pieces and includes contact metallisation regions. The semiconductor body produces an electric field that emerges from an edge region. Passivation means includes a first or radially inner part in contact with the edge region of the semiconductor body and which diffuses the electric field as it emerges from the edge region and a second or radially outer part. The second part of the passivation is in contact with the first part and provides a substantially void-free interface with the profiled surface of each pole piece. The device may be immersed in a dielectric liquid.

Abstract: The present invention provides an improved single-layer coil for a rotating or linear electrical machine. The coil has a first endwinding that is substantially straight to a longitudinal axis of the coil and a second endwinding that is bent relative to the longitudinal axis of the coil. The coil therefore has differently shaped endwindings with one end 12 being ‘straight’ and the other end being ‘bent.

Abstract: The system (21) includes: a power transistor (22), a data medium (60) including data relating to the manufacturing tolerance (Tol) of at least one electric parameter of the transistor (22), an electric circuit (26) for controlling the transistor adapted so as to operate for a reference value of the parameter (VREF), an electric circuit (64) having an inductance of less than 100 nH and such that the assembly (70) formed with the circuit (64) and the transistor (22) has a value for the parameter, for which the deviation in absolute with the reference value is strictly less than the manufacturing tolerance (Tol).

Abstract: A wind turbine generator has a drive end at which one or more turbine blades are mountable and a non-drive end. The wind turbine generator comprises an external stator having a radially inner surface and an internal rotor having a radially outer surface, an air gap being defined between the rotor and the stator. A main bearing arrangement is provided at the drive end and acts between the rotor and the stator to mount the rotor for rotation about the stator and a stabiliser beating is provided at the non-drive end and acts between the rotor and the stator to stabilise the rotor and stator and maintain and control the air gap therebetween.

Abstract: A power supply system for a charge is provided. The power supply system includes a converter connected in input to a current source and in output to a charge, the converter being able to deliver a direct current to the charge and allow the circulation of the current in a single direction, from the current source to the charge and a circulation bus for an electric current, including a first end and a second end. The power supply system further includes a device for injecting an additional alternating voltage and at the second end of the circulation bus, the injection device being connected to the second end and a device for recovering the additional injected alternating voltage, the recovery device being connected between the first end of the bus and the charge, so as to supply the charge with electrical current.

Abstract: A wind turbine typically includes a generator and a rotating mechanical system having a natural period. The present invention relates to a method of controlling generator torque that minimises oscillations in the speed of the generator rotor. In the event of a grid fault or transient, or a fault in the power converter, the generator torque is decreased at a substantially constant rate with respect to time as shown in graph (c). The rate at which the generator torque is decreases is proportional to the nominal rated torque of the generator and inversely proportional to an integer multiple of the natural period of the rotating mechanical system.

Abstract: An electric machine, for example, a motor, is provided. The machine or motor includes a stator, a rotor, at least one main bearing for supporting the rotor relative to the stator in a main range of speeds and at least one secondary bearing suitable for supporting the rotor relative to the stator when the first main bearing is faulty. Each secondary bearing is a passive electrodynamic bearing and includes at least one permanent magnet and a moveable electric conductor element.

Abstract: The invention relates to a component such as a rotor or stator for an electrical machine. The component includes a plurality of axially adjacent stacks of laminations. At least one pair of adjacent stacks are spaced apart in the axial direction by spacer means such that a passageway or duct for cooling fluid, e.g. air, is formed therebetween. The spacer means comprises a porous structural mat of metal fibres. The cooling fluid may flow through the spaces or voids between the fibres.

Abstract: In a marine power distribution and propulsion system with a medium voltage distribution busbar (MVAC1) and a low voltage distribution busbar (LVAC1) then a rectifier (SC) is controlled, optionally to provide active filtering and static compensation benefits. A common power supply system incorporating ac generators (G1-G4) supplies power to the medium and low voltage distribution busbars. The rectifier (SC) is connected to the medium voltage distribution busbar (MVAC1). A controller (Co) uses feedback signals indicative of electrical quantities of the distribution voltages carried by both the medium voltage and low voltage distribution busbars (MVAC1, LVAC1) to control the rectifier (SC) to regulate electrical quantities at the ac terminals of the rectifier (SC) in order to achieve desired electrical quantities of the distribution voltage carried by the low voltage distribution busbar (LVAC1).

Abstract: An assembly includes an electrical machine connected to a power converter by a three-phase circuit having three conductors, e.g. cables. Each conductor is associated with a switching device such as a contactor or the like that connects the conductor to a common conductor or terminal. In the event of a fault current being developed in the circuit or the power converter, the switching devices are operated to close the fault current and connect together the conductors or the three-phase circuit to provide a full three-phase short circuit.