Abstract: A heat sink is disclosed including a cold plate, a plurality of heat pipes, and a plurality of fins. The cold plate has a first surface arranged substantially vertical and adapted to thermally couple to a heat source. Each of the plurality of heat pipes have an evaporator section arranged substantially vertical and thermally coupled to the cold plate, a condenser section arranged at an incline, and a single bend section coupling the evaporator section and the condenser section. The plurality of fins are thermally coupled to the condenser sections of the plurality of heat pipes.

Abstract: A heat sink is disclosed including a cold plate, a plurality of heat pipes, a plurality of fins, and a heating unit. The cold plate has a first surface adapted to thermally couple to a heat source. Each of the heat pipes has an evaporator section thermally coupled to the cold plate and a condenser section coupled to the evaporator section. The plurality of fins are thermally coupled to the condenser sections of the plurality of heat pipes. The heating unit is adapted to heat condenser sections of a subset of the plurality of heat pipes.

Abstract: A method of manufacturing a coil support member in which a thermosetting or thermoplastic material is introduced into a mould cavity and hardened, wherein one or more components are positioned within the mould cavity during the manufacturing process before the thermosetting or thermoplastic material is introduced, the components are then embedded in the thermosetting or thermoplastic material and form an integral part of the coil support member, and one or more functional filler materials are added to the thermosetting or thermoplastic material to improve the thermal matching between the integral components and the thermosetting or thermoplastic material.

Abstract: A system for converting a first electric voltage into a second electric voltage, comprising: at least two input terminals and two output terminals; and switching members disposed between the terminals, which can convert the first voltage into the second voltage. At least one switching member comprises at least two arms connected in parallel and each arm includes an electronic switch that can be controlled such as to occupy either an on-state or an off-state, said switch comprising a control electrode and two conduction electrodes that conduct current in the on-state. The switching member comprises a common control terminal connected to the control electrode of the switch of each arm, as well as a first common conduction terminal and a second common conduction terminal connected respectively to a first conduction electrode and a second conduction electrode of the switch of each of the arms.

Abstract: A method is described for controlling a plurality of parallel-connected power converters 20a, 20b, each of which operates in accordance with a pulse width modulation (PWM) strategy defined by an independent voltage carrier signal and an independently controllable modulating sinusoidal voltage signal which are used to generate a PWM command signal for each PWM strategy. The voltage carrier signals of the PWM strategies have the same switching period and desynchronisation of the PWM command signals causes an unwanted circulating current to flow between the power converters 20a, 20b. The method thus comprises providing the independently controllable modulating sinusoidal voltage signal of the PWM strategy of at least one of the plurality of power converters 20a, 20b with a dc voltage offset to modify the PWM command signal of the at least one power converter and thereby increase the synchronisation of the PWM command signals so that the magnitude of any unwanted circulating current is reduced.

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 bearing 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 rotating electrical machine comprises a rotor having an axis of rotation and a stator assembly surrounding the rotor. The stator assembly comprises a plurality of circumferentially arranged stator segments and a plurality of link elements of which at least one link element extends between each of the circumferentially adjacent stator segments. Each link element provides a rigid circumferential connection between circumferentially adjacent stator segments so that the linked stator segments form a torsionally stiff annular stator and also provides a radially flexible connection between circumferentially adjacent stator segments to permit relative movement between adjacent linked stator segments in the radial direction.

Abstract: The present invention relates to a vertical axis wind turbine having a vertical support tower. At least one aerofoil or blade is mounted for rotation about the support tower. An electrical machine, typically a permanent magnet generator includes a rotor assembly and a stator assembly. The at least one aerofoil is secured to the rotor assembly such that rotation of the aerofoil about the support tower causes rotation of the rotor assembly relative to the stator assembly. The stator assembly is formed as a structural component of the support tower and defines part of a vertical access passage that extends through the support tower to provide access for maintenance and repair.

Abstract: A rotor (or a stator) for a superconducting electrical machine includes a mounting that is maintained at substantially ambient temperature during operation of the electrical machine and a field coil support structure. A plurality of superconducting field coils are maintained at cryogenic temperatures during operation of the electrical machine and are supported by the field coil support structure. At least one coupling element is used to fix the field coil support structure to the mounting. The field coil support structure is preferably fixed to the mounting by a plurality of substantially circumferentially extending coupling elements at a first and second axial end of the field coil support structure and the mounting such that the mounting and field coil support structure are substantially separated over their axial lengths by a vacuum gap.

Abstract: An offshore wind farm includes a plurality of wind turbines connected to an onshore converter station by means of a distributed power transmission system. The power transmission system includes a series of offshore converter platforms distributed within the wind farm. Each converter platform includes a busbar carrying an ac voltage for the converter platform and to which the wind turbines are connected. Each converter platform also includes one or more converter transformers connected to the busbar and a series of one or more converter modules. The power transmission system includes dc transmission lines which deliver generated power back to the onshore converter station.

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: In an oscillating water column (OWC) assembly power may be generated based on a power reference that is derived from an estimate of the available mechanical power in the air turbine 2 or a measured pressure drop across the turbine. The power reference is used to derive a power control torque reference within a power controller 14. A speed controller 16 uses a comparison of a measured speed of the generator 8 and a maximum speed limit to derive a speed control torque reference. A selector function 22 selects whichever of the power control and speed control torque references is the maximum at any time instant. The selected torque reference is input to an anti stall torque function 24 where it is selectively modified by applying a speed dependent gain that decreases with decreasing turbine speed, preferably so that the main torque reference is zero for a minimum speed limit.

Abstract: The present invention relates to power distribution systems (e.g. a marine power distribution and propulsion system) that include first and second ac distribution busbars. The first ac distribution busbar will typically be a medium voltage busbar for the propulsion drive systems and the second ac distribution busbar will typically be a low voltage for ships services. A 12-pulse rectifier has its ac terminals electrically connected to the first ac distribution busbar. A multiple output generator has first and second galvanically-isolated stator windings. The first stator winding provides a six-phase ac output and is connected to the first ac distribution busbar. The second stator winding provides a three-phase ac output and is connected to the second ac distribution busbar. The six-phase ac output is phase shifted relative to the three-phase ac output to reduce the problematic coupling of harmonic distortion between the first and second ac distribution busbars.

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 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 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 torsional vibration damper is integrated into a rotating electrical machine. A rotatable assembly of the electrical machine includes a rotor core pack having a first end and a second end, The integrated torsional vibration damper consists of a torsional elastic coupling and a torsional elastic damper and provides mechanical damping. The integrated torsional vibration damper is mounted to the rotatable shaft of the electrical machine by a flange. The rotor core pack is mounted at the first end to the integrated torsional vibration damper by suitable structure members such as a mounting flange and is not fixedly mounted directly to the rotatable shaft. In the case where the rotor core pack is cooled by circulating coolant fluid (e.g. MIDEL) then the integrated torsional vibration damper may be a viscous damper that uses the coolant fluid as a viscous working, fluid.

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: 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.