Abstract: A method of controlling a permanent magnet synchronous electric machine (PMSM) drive using a Deadbeat Predictive Current Control (DBPCC) scheme is provided. The method comprises: determining d-axis and q-axis stator current values (id, iq) representative of a measured PMSM current; determining d-axis and q-axis reference current values (id*, iq*); based on the stator current values (id, iq) and the reference current values (id*, iq*), determining d-axis and q-axis current correction values (Cd, Cq); determining corrected reference current values (id**, iq**) as a sum of the reference current values (id*, iq*) and the current correction values (Cd, Cq); and controlling the PMSM drive using the corrected reference current values (id**, iq**) as reference current inputs of the DBPCC scheme. A controller for performing the method; a system comprising the controller, a PMSM and associated power electronics; and a computer program for performing the method are also provided.

Abstract: An oil system for an aircraft propulsion system. The aircraft propulsion system comprises a motor configured to drive a propulsor via a reduction gearbox. The oil system comprises a first feed line configured to supply cooling oil to the reduction gearbox, a second feed line configured to supply cooling oil to a further oil cooled component, and an air-cooled oil cooler. The air-cooled oil cooler is provided upstream of the first feed line to provide cooled oil to the reduction gearbox; and the second feed line is configured to bypass the air-cooled oil cooler to cool the further oil cooled component.

Abstract: A manufacturing method includes: in a loom, weaving a woven reinforcing fibre fabric including a plurality of reinforcing fibre tows and polymeric material; and heating the woven reinforcing fibre fabric as it exits the loom to cause the polymeric material to melt and/or cure.

Abstract: An apparatus for manufacturing an annular or semi-annular composite component having a circumferentially-extending base and a flange, the apparatus including: a loom for weaving a woven preform of fibre reinforcement material for the composite component; a rotatable mandrel configured to receive and draw the woven preform through the loom for weaving; and a guide disposed between the loom and the rotatable mandrel, configured so that a woven preform drawn by the rotatable mandrel along a guide path under tension engages the guide to transition to a flanged profile at a lip of the guide before being received on the mandrel.

Abstract: A manufacturing method comprises: providing a woven fabric comprising a plurality of reinforcing fibre tows and a plurality of thermoplastic polymer yarns woven together; and moulding the woven fabric in a heated mould to form a preform for a composite component.

Abstract: A method of training a neural network to generate conversational replies, the method including: providing a first dataset of stored phrases linked to form a plurality of conversational sequences; training the neural network to generate responses to input phrases using the first dataset; and using the trained neural network to generate a list of conversational replies in response to conversational inputs.

Abstract: The disclosure relates to an electrical power system for providing a stabilised DC voltage to a power bus. Example embodiments include an electrical power system comprising: a DC power bus having first and second DC power bus terminals; an electrical storage unit having first and second terminals, the second terminal connected to the second DC power bus terminal; a DC:DC converter having first and second DC:AC converters and a transformer connected between the first and second DC:AC converters, the first DC:AC converter connected between the first terminal of the electrical storage unit and the first DC power bus terminal; and a controller connected to control a switching operation of one or both of the first and second DC:AC converters.

Abstract: A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.

Abstract: A novel configuration for an axial flow gas turbine engine for an aircraft has an engine core having a core length and including a first turbine, an axial compressor, and a drive connecting the first turbine to the axial compressor, the engine core further including a second turbine, and a fan shaft connecting the second turbine to a fan located upstream of engine core, the fan including a plurality of fan blades extending from a fan hub, the fan having a tip radius from 90 mm to 225 mm and wherein the ratio of fan tip radius to engine length is 0.15 to 0.25. The engine may have 3, 4 or 5 compressor stages and a combustor volume (in litres) which when divided by the fan tip radius (in mm) is 0.015 to 0.083. The fan may be multistage fan configured to permit electric motor to be located within fan hub diameter.

Abstract: A combustor casing component for a gas turbine engine which is manufactured as a single-piece. The combustor casing component has a combustor outer casing portion, an outlet guide vane outer case portion, a pre-diffuser portion, a plurality of outlet guide vanes, and an outlet guide vane inner case portion.

Abstract: A novel configuration for axial flow gas turbine engine for aircraft has an engine core having a core length and including first turbine, axial compressor, and drive connecting the first turbine to the axial compressor, the engine core further including a second turbine, and a fan shaft connecting the second turbine to a fan located upstream of the engine core, the fan including a plurality of fan blades extending from a fan hub, the fan having a tip radius from 90 mm to 225 mm and wherein the ratio of fan tip radius to an engine length is 0.15 to 0.25. The engine may have 3, 4 or 5 compressor stages and a combustor volume (in litres) which when divided by the fan tip radius (in mm) is 0.015 to 0.083. The fan may be a multistage fan configured to permit an electric motor to be located within the fan hub diameter.

Abstract: An engine for an aircraft includes an engine core having a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan having a plurality of fan blades; and a gearbox. The gearbox is an epicyclic gearbox and comprises a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The radial bending stiffness of the planet carrier is equal to or greater than 1.20×109 N/m, and/or the tilt stiffness of the planet carrier is greater than or equal to 6.00×108 Nm/rad. A method of operation of such an engine is also disclosed.

Abstract: There is disclosed a composite fan blade root 100 comprising an outer region 110 comprising composite material and defining an outer inspection surface 120 of the component; an inner region 108 surrounded by the outer region 110; and an internal reflection boundary 102 embedded within the root 100 between the inner region and the outer region. The reflection boundary is configured to change a velocity of a signal emitted into the root from the inspection surface, whereby a signal emitted into the root from the inspection surface 120 may be reflected for detection.

Abstract: A rotor assembly includes a plurality of segmented magnets disposed about an outer surface of a rotor core and a plurality of segmented metallic bands configured to secure the plurality of segmented magnets to the outer surface of the rotor core. The number of segments of the segmented metallic bands in an axial direction is greater than the number of segments of the segmented magnets.

Abstract: The disclosure relates to an electrical power system for connecting an electrical machine to first and second DC networks operating at different voltages. In an embodiment, an electrical power system comprises: an electrical machine having first, second, third and fourth windings; first, second, third and fourth AC:DC power electronics converters each connected to receive an input AC supply from the respective first, second, third and fourth windings, each AC:DC power electronics converter having first and second DC output terminals connecting the AC:DC power electronics converters to first, second and third DC supply output terminals, wherein the first and second windings are arranged to provide an AC supply to the respective first and second AC:DC power electronics converters in quadrature to each other and the third and fourth windings are arranged to provide an AC supply to the respective third and fourth AC:DC power electronics converters in quadrature to each other.

Abstract: The disclosure relates to an electrical power system for connecting an electrical machine to first and second DC networks operating at different voltages. Example embodiments include an electrical power system comprising: an electrical machine having first and second pluralities of windings; a first AC:DC power electronics converter connected to the first plurality of windings; a second AC:DC power electronics converter connected to the second plurality of windings; a switching controller configured to provide switching signals to the first and second AC:DC power electronics converters to provide a first DC supply at a DC side of the first AC:DC power electronics converter and a second DC supply at a DC side of the second AC:DC power electronics converter.

Abstract: In some examples, a system including a fluid stream monitoring system. The monitoring system includes an illumination device configured to illuminate at least some of particles suspended in a fluid stream; and an imaging device configured to image the illuminated particles at a first image plane that intersects a longitudinal axis of the fluid stream, wherein the illumination device and the imaging device are registered to the fluid stream delivery device in the first image plane, where the first image plane is substantially orthogonal to the longitudinal axis. The system includes processing circuitry configured to determine one or more physical characteristics of the fluid particles.

Abstract: A cutting electrode head for a handheld electrical discharge machining (EDM) device comprising: a housing; a cutting electrode supported in the housing, and configured to move from a retracted position to an extended position along an electrode axis (C) to cut a workpiece; and an actuator supported in the housing and movable along a movement axis (E) which is at an angle to the electrode axis (C), wherein movement of the actuator along the movement axis (E) causes the cutting electrode to move between its retracted and extended positions.

Abstract: A storage tank for liquid hydrogen comprises first and second shells each constructed of laminate material, the second shell being disposed outwardly of the first shell with respect to the centre of the storage tank. The first and second shells are mechanically connected by a first plurality of pins each of which passes through at least some layers of the second shell and at least some layers of the first shell. The storage tank may be constructed using a simpler manufacturing process involving less tooling and fewer process steps than is the case for known tanks for storing liquid hydrogen. The storage tank has also has a lower mass and reduced thermal losses compared to tanks of the prior art. The plurality of pins allows for the shells to be thinner, and hence lighter, than similar shells in tanks of the prior art.

Abstract: A gas turbine engine includes: a combustor that combust the fuel and having an exit, a combustor exit temperature (T40) is the average temperature of flow and a combustor exit pressure (P40) is the total pressure there; a turbine including a rotor having a leading edge and a trailing edge, and wherein a turbine rotor entry temperature (T41) is an average temperature of flow at the leading edge and a turbine rotor entry pressure (P41) is the total pressure there; and a compressor having an exit, wherein a compressor exit temperature (T30) is the average temperature of flow at the exit from the compressor and a compressor exit pressure (P30) is the total pressure there (all at cruise conditions). A method of determining at least one fuel characteristic includes changing a fuel supplied to the engine; and determining a change in a relationship between T30 or P30, T40 and T41, or of P40 and P41, respectively.