Abstract: An electrical machine 20, 48 comprises a first stator 22 and a second stator 24 spaced from the first stator 22, at least one of the first stator 22 and the second stator 24 including a guide arrangement 26, 50. The electrical machine 20, 48 also includes a plurality of rotor elements 30, 46 located between the first stator 22 and the second stator 24 and cooperating with the guide arrangement 26, 50 for movement relative to the first stator 22 and the second stator 24. Adjacent rotor elements 30, 46 cooperate with each other so that the rotor elements 30, 46 form a rotor and at least one of the rotor elements 30, 46 includes a coupling element 32 to transfer force to or from the rotor.

Abstract: The present invention provides a method of controlling the position of a spread moored marine vessel (1). In particular, the method of the present invention substantially maintains the position of a spread moored vessel (1) in, or on the boundary of a target area (2) using thruster assistance. This is done by monitoring the position of the vessel and when the vessel (1) is positioned outside of the target area (2) applying a position correcting thrust (7) to the vessel (1) in the direction of an aim position located on the boundary of the target area (2) and when the vessel (1) is positioned within the target area (2) reducing the position correcting thrust (7) applied to the vessel (1) or maintaining the position correcting thrust (7) applied to the vessel (1) at zero. The present invention may also apply a damping thrust (7) to the vessel (1) in order to damp the positional variation of the vessel (1).

Abstract: A propulsion chain (8) for a ship (6) including a main heat engine (18); at least one secondary electrical power house (26) powering a distribution panel (34); at least one transmission line (16) provided with an end propeller (14) and mechanically coupled to the main heat engine (18) to drive the latter; at least one rotating electrical machine (22) mechanically coupled to the transmission line (16) and powered from the distribution panel (34), a mechanical coupler (20) able to be freed from the main heat engine (18) and the rotating electrical machine (22) arranged on the transmission line (16), between the rotating electrical machine (22) and the main heat engine (18).

Abstract: A method is provided for controlling cold rolling of a sheet metal strip involving continuously passing the strip in at least two successive rolling stands, each stand including at least two driven rolls between which the strip moves and is plated. The method includes estimating the slippage variation in output of one rolling stand; and correcting the rotation speed of the rolls of at least one corrected rolling stand based on the estimated slippage variation.

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 method for operating an electrical circuit, in particular of a converter is described. The circuit, in at least one embodiment, includes a line-side converter that is coupled to a capacitor. The line-side converter includes at least two series connections, each including at least two power semiconductor elements, and each of the at least two series connections being connected parallel to the capacitor. The line-side converter is coupled to an energy supply system. The DC voltage that is present at the capacitor is determined. A maximum voltage is predetermined. If the DC voltage present at the capacitor is determined to be greater than the maximum voltage, then at least two of the power semiconductor elements are switched into their conductive state in such a manner that the capacitor is discharged in the direction of the energy supply system.

Abstract: A permanent magnet arrangement for an electrical machine comprises a support structure for carrying magnetic flux and a pole assembly fixed to the support structure. The pole assembly comprises a magnet pole comprising at least one piece of permanent magnet material and a magnet carrier on which the magnet pole is mounted and which provides a magnetic flux path between the magnet pole and the support structure. The permanent magnet arrangement further comprises a sleeve containing the magnet pole and at least part of the magnet carrier. The magnet carrier is secured to the support structure to fix the pole assembly to the support structure and the sleeve is clamped to the support structure by the magnet carrier. A method for assembling the permanent magnet arrangement is also described.

Abstract: A bus bar assembly includes a first main conductor, a second main conductor, and an insulator member provided between the main conductors. The insulator member includes: (i) an insulator component, (ii) a first conductor layer provided on the top surface of the insulator component, and (iii) a second conductor layer provided on the bottom surface of the insulator component, wherein the first conductor layer includes an outer edge around a perimeter thereof, wherein the outer edge is located at least a certain distance from the outer edge around the perimeter of the insulator component, wherein the second conductor layer includes an outer edge around a perimeter thereof, wherein the outer edge is located at least the same certain distance from the outer edge of the insulator component, and wherein the certain distance is sufficient to cause the bus bar assembly to satisfy the creepage requirement of the assembly.

Abstract: A power transmission and distribution system suitable for subsea electrical loads includes a primary dc transmission cable connected to an onshore AC/DC converter module that connects the onshore end of the cable to an ac supply network. The subsea end of the cable is connected to a primary subsea power distribution unit and includes a DC/DC converter module having a modular topology with a series of interconnected DC/DC converter units. The DC/DC converter module is connected between the cable and a primary dc distribution network. Secondary dc transmission cables and associated circuit breakers connect the primary subsea power distribution unit to secondary subsea power distribution units that are located near the subsea loads. Each secondary subsea power distribution unit includes a DC/DC converter module having a modular topology with a series of interconnected DC/DC converter units. Respective secondary dc distribution networks supply power to one or more subsea loads.

Abstract: An electronic system with component redundancy includes a first processing unit, connected to a first board, and a second processing unit redundant with respect to the first unit, and connected to a second board redundant with respect to the first board. Each processing unit and each board include a first communication port, the first communication ports of the first unit and of the first board, and, respectively, of the second unit and of the second board, being interconnected by a wired communication link. Each processing unit and each board include a second communication port, the second port of the first board being connected to the second port of the second unit by a wired communication link, and the second port of the second board being connected to the second port of the first unit by a wired communication link, each communication port able to be activated or deactivated by a corresponding software command.

Abstract: The invention relates to a 3N?4-level (N?3) voltage converter including: 3N?5 direct voltage generators (1, 2, 3, 4) connected between two input voltage terminals (V+, V?), two lateral commutation branches (10, 11), each connected between an output terminal and an input voltage terminal (V+, V?) and comprising N?1 series connected commutation cells (20, 21, 22, 23), 2N?4 central commutation branches (12, 13), each comprising a switch bidirectional in terms of voltage and current and being connected between two commutation cells of a lateral branch (10, 11) and two generators, and N?2 pairs of diode cells (16) each connected to two of the 2N?4 central commutation branches (12, 13). The diodes (14, 15) of one pair are series connected, in the same direction, and are connected together by a middle point connected between two generators.

Abstract: The present invention provides a permanent magnet rotor arrangement for a rotating electrical machine including a rotor body having an outer rim. A circumferential array of magnet carriers is mounted to the rotor body by fixing members and support members and is spaced apart from the rotor body in the radial direction to define a series of axially gaps or spaces which can optionally be used as passages for cooling air. At least one pole piece made of permanent magnet material is located adjacent to a surface of each magnet carrier. The magnet carriers and pole pieces preferably have a laminated or divided construction to virtually eliminate eddy currents that may be particularly problematic in certain types and construction of electrical machine. The flux path between adjacent pole pieces flows in the circumferential direction within the magnet carriers and does not use the rotor body.

Abstract: A method is described for controlling a plurality of power converters 1, 2 connected in parallel between an ac arrangement 12 and a common dc link 16, each of the power converters 1, 2 operating in accordance with a pulse width modulation (PWM) strategy and having an independently variable dc link reference voltage. The method comprises modifying an output voltage droop characteristic of at least one of the plurality of parallel-connected power converters 1, 2 by varying the dc link reference voltage of the at least one power converter 1, 2 based on the output current of the at least one power converter 1, 2 and the average of the output currents of the plurality of power converters 1, 2.

Abstract: A permanent magnet arrangement for an electrical machine comprises a support structure for carrying magnetic flux and a pole assembly fixed to the support structure. The pole assembly comprises a magnet pole comprising at least one piece of permanent magnet material and a magnet carrier on which the magnet pole is mounted and which provides a magnetic flux path between the magnet pole and the support structure. The permanent magnet arrangement further comprises a sleeve containing the magnet pole and at least part of the magnet carrier. The magnet carrier is secured to the support structure to fix the pole assembly to the support structure and the sleeve is clamped to the support structure by the magnet carrier. A method for assembling the permanent magnet arrangement is also described.

Abstract: The present invention relates to armature windings for DC electrical machines, and in particular to those that use electronic commutation and have relatively few slots per pole-pair. The armature windings are particularly well suited for use with rotating DC electrical machines that have a large diameter and a large number of poles such as those that might be directly coupled to the turbine blade assembly of a wind turbine. The armature winding is arranged in relation to the magnetic field generated by a field winding or by permanent magnets such that a number of commutation events during the time taken for the relative movement between the armature and the field system of one pole-pair is much larger than the number of coils per pole-pair.

Abstract: A power collection and transmission system can be used with a plurality of energy devices such as off-shore wind turbines. The energy devices are grouped into two or more clusters. The system includes a dc collection network for each cluster. A primary DC/DC converter is located at each energy device and is connected to the dc collection network. First and second dc transmission lines are used to transmit any power generated by the energy devices to an on-shore converter station. A secondary DC/DC converter assembly is connected between the dc collection networks and the first and second dc transmission lines.

Abstract: A method of controlling a plurality of power converters 1a, 1b and 1c can be used to interface to a supply network, ac busbar etc. Each power converter includes a network bridge 14 operating in accordance with a pulse width modulation (PWM) strategy having the same switching period and which causes at least one unwanted harmonic in the supply network voltage. The method includes the step of providing the switching period of the PWM strategy of each network bridge with a different time offset relative to a time datum such that the at least one unwanted harmonic in the supply network voltage is at least partially cancelled. Two alternative ways of providing the time offset are described.

Abstract: A support structure is used to mount the stator of a rotating electrical machine (e.g. a motor or generator). The support structure includes a rigid external support frame (6). To minimise the transmission of vibrations caused by stator electromagnetic forces into the external support frame (6), at least one sandwich anti-vibration mount (14a) is secured between the external support frame (6) and a part of the stator (28). The mount (14a) is oriented relative to the stator such that it experiences compression loading in a substantially tangential direction of the stator and radial shear loading in a substantially radial direction of the stator during operation of the rotating electrical machine. The sandwich anti-vibration mount (14a, 14b) is pre-loaded with a pre-determined compression load substantially along its compression axis (Ac).

Abstract: Described is a method for starting up a system for generating electrical power. The system includes a turbine that is mechanically connected to a generator, while the generator is electrically connected via a converter to a load, in particular to a power supply grid. The generator includes a total number of windings. With at least one embodiment of the method, a number of generator windings are combined at low rotational speeds of the turbine, wherein the combined number of windings is less than the total number of windings.

Abstract: The present invention relates to a fuse assembly for rapid interruption of a prospective fault current. The fuse assembly includes a plurality of splitter plates. A plurality of foil elements extend between a pair of terminals and are physically supported by the splitter plates. A pair of parallel busbars are in series with the foil elements and generate a magnetic field that is substantially perpendicular to the current flowing in the foil elements. In the presence of a prospective fault current, the foil elements will melt and at arcing inception an electromagnetic force developed as a result of interaction between the magnetic field and the arc current will push the molten foil elements into the splitter plates. This increases the arc length and hence the arc voltage. At least the foil elements and the splitter plates are preferably located in flowing liquid dielectric such as MIDEL 7131, for example.