Abstract: A synchronous electrical machine comprises a plurality of phases and detecting means arranged to detect an open-circuit fault in at least one of the phases of the synchronous electrical machine. Isolating means is arranged to isolate the at least one phase of the synchronous electrical machine with the fault. Phase shift means are arranged to produce a controlled phase shift between the voltage and the current within the remaining phases of the synchronous electrical machine so as to adjust the phase angle of the second harmonic powers produced by the remaining phases of the synchronous electrical machine such that the vector sum of the second harmonic power vectors of the remaining phases of the synchronous electrical machine is zero to eliminate torque ripple. The phase shift means is arranged to adjust the phase angle of all the remaining phases by the same predetermined angle to maximise the torque ripple-free power output of the synchronous electrical machine.

Abstract: Electrical power generation systems typically comprise an electrical power distribution arrangement in which a number of electrical power generators are coupled in parallel. In such circumstances in order to avoid conflict generally a first electrical power generator is controlled with a voltage controller while second electrical power generators have electrical current controllers. As loads are switched into and out of the electrical distribution system in normal operation the first electrical power generator and its voltage controller can accommodate voltage dynamics and therefore maintain a desired voltage. However, in order to accommodate heavier loads switching, the dynamic operation of the electrical current controller is achieved through utilizing operational voltage margins from a desired voltage as control signals to the electrical current controller.

Abstract: The invention relates to a method of actuating by means of a wax actuator and to a wax actuator. The wax actuator (10, 100, 200) includes a wax expansion generator comprising a housing (12) defining a chamber (18) which is partially filled with wax (20.1) and partially filled with hydraulic fluid, the wax (20.1) and the hydraulic fluid being separated by at least one sealing interface (20.2, 202), and heating means (22) for heating the wax (20.1) to cause it to melt and expand. The wax actuator (10, 100, 200) further includes a hydraulic transmission device comprising a hydraulic line (38) in communication with the hydraulic fluid within the chamber (18) and a connector (40) at a downstream end of the hydraulic line (38) for use in connecting the hydraulic line (38) to a working object.

Abstract: Electrical machine arrangements have advantages with regard to providing local electrical power and starting. Embedding such electrical machine arrangements in machinery such as gas turbine engines is advantageous in removing mechanical linkages and reducing aerodynamic drag. However, the components utilised must be able to withstand harsh environmental conditions and therefore the DC link capacitor used for smoothing of voltage fluctuations are limited to relatively low capacitance densities. Low density DC link capacitors require large sizes which render electrical machines less acceptable for embedded usage. By providing offset of electrical current in inductance elements such as stator windings and stator coils of electrical machines in dead periods of the cycle a reduction in DC link capacitor requirements is achieved reducing the size, weight and complexity of installing electrical machines in gas turbine engines.

Abstract: Electrical power generation systems typically comprise an electrical power distribution arrangement in which a number of electrical power generators are coupled in parallel. In such circumstances in order to avoid conflict generally a first electrical power generator is controlled with a voltage controller whilst second electrical power generators have electrical current controllers. As loads are switched into and out of the electrical distribution system in normal operation the first electrical power generator and its voltage controller can accommodate voltage dynamics and therefore maintain a desired voltage. However, in order to accommodate heavier loads switching, the dynamic operation of the electrical current controller is achieved through utilising operational voltage margins from a desired voltage as control signals to the electrical current controller.

Abstract: Utilisation of a number of electrical machines such as generators all driven by a common prime mover, such as a gas turbine engine, are known. However, faults in one phase of one particular electrical machine may cause torque vibration and therefore stressing to mechanical linkages between the electrical machine and the prime mover. By determining torque vibration and then utilising a second electrical machine to introduce an anti-phase torque vibration a substantially balanced and steady torque loading to the mechanical linkages can be achieved.

Abstract: Within generator systems maintenance of stability in terms of voltage is desirable. Generally, several generators will be arranged in parallel within the generator system with one generator voltage controlled to provide dynamic responsiveness to load switching. With regard to some loads which are generally of an active nature, the capacity of a first generator, which is voltage controlled, may be insufficient to adequately avoid transient voltage instability. By providing an actuator signal from a load to act as a pre-emptive or forward feed to an electrical current controlled generator, that second electrical current generator can be arranged to provide additional or reduced electrical current to avoid system voltage instability.

Abstract: An apparatus comprised of a power source, a set of primary loads, a set of life extension loads, and a controller. The power source is capable of supplying power and the set of primary loads is capable of being operated using the power. The set of life extension loads is capable of being operated using the power and capable of extending life of the set of primary loads. The controller is capable of controlling an operation of the set of primary loads and the set of life extension loads to optimize a total systems operating metric consisting of performance, energy use, and life to reduce a total cost.

Abstract: An electrical power system includes an alternating current (AC) power source configured to output an AC signal, a single phase pulse-width modulated (PWM) rectifier coupled to the AC power source and to an electrical load; a DC link capacitor coupled in parallel to the load and the PWM rectifier; and an active ripple energy storage circuit.

Abstract: A method of determining common three-dimensional structural features of protein surfaces is provided, as is use of representations of these common structures in molecular database searching and in designing focused molecular libraries. The method is particularly concerned with the analysis and representation of protein surfaces such as b-turns, loops and contact surfaces. In one form, the method identifies common locations and orientations of amino acid side-chains, simplified as C?-C? vectors. In another form, the method identifies common regions of surface charge represented by grid points in three-dimensional space. Further provided are common three dimensional structural features of proteins that can be used to search molecular databases for the purposes of identifying molecules that match these common three dimensional structural features.

Abstract: An earthing arrangement for a DC electrical system (10), the electrical system (10) comprises a plurality of earthing points (24A, 24B, 24C) and each earthing point (24A, 24B, 24C) is directly and permanently connected to earth (26) by a high impedance connection (28A, 28B, 28C). Each earthing point (24A, 24B, 24C) is selectively connectable to earth (26) in electrical parallel with the high impedance connection (28A, 28B, 28C) by a solid connection (30A, 30B, 30C) and a switch (32A, 32B, 32C). In first mode of operation the switch (32A) between the earthing point (24A) and the earth (26) of only one of the plurality of earthing points (24A, 24B, 24C) is closed.

Abstract: Silicon-based high pressure sensor modules are manufactured in an array arrangement, incorporating a low temperature cofired ceramic (LTCC) substrate. The LTCC substrate can withstand high pressures. Bossed containers filled with oil are mounted on the substrate in an array. These bossed containers house the sensor cells which are composed of a sensor handle wafer and a diaphragm. The top surface of these bossed containers are flexible and deflect under pressure. By controlling the surface area and the thickness of the top surface, the pressure sensors can be configured to measure a wide range of pressures. The oil transfers pressure from the bossed container to the diaphragm of the sensor cell while protecting the sensor cell from high pressures and harsh media.

Abstract: A sensor module is provided having a compact housing containing a sensor. A low temperature co-fired ceramic substrate is located on the housing. The sensor and signal processing circuitry are located on the low temperature co-fired ceramic substrate. The sensor module further includes a metal shield substantially encapsulating the sensor.

Abstract: A silicon-based high pressure sensor module incorporates a low temperature cofired ceramic (LTCC) substrate. The LTCC substrate can withstand high pressures. A bossed container filled with oil is mounted on the substrate and houses a sensor cell. The top surface of the bossed container is flexible and deflects under pressure. By controlling the surface area and the thickness of the top surface, the pressure sensor can be configured to measure a wide range of pressures. The oil transfers pressure from the bossed container to the diaphragm of the sensor cell while protecting the sensor cell from high pressures and harsh media.

Abstract: A technique for manufacturing an integrated pressure sensor includes a number of steps. Initially, a substrate with conductive electrical traces located on first and second sides of the substrate is provided. A plurality of compensation circuits are positioned in an array on the first side of the substrate in electrical contact with one or more of the conductive electrical traces on the first side of the substrate. A plurality of pressure sensors are positioned on the second side of the substrate in electrical contact with one or more of the conductive electrical traces on the second side of the substrate. Each one of the sensors is associated with one of the compensation circuits to form a plurality of pressure sensor-compensation circuit pairs. The substrate includes conductive vias to electrically connect each of the sensor-compensation circuit pairs. Each of the compensation circuits provides temperature compensation for an associated one of the sensors.

Abstract: The invention relates to a group of novel piperazine and piperidine derivatives of the formula wherein Y is hydrogen, halogen, alkyl (1-3C), or CN, CF3, OCF3, SCF3, alkoxy(1-3C), amino or mono- or dialkyl(1-3C) substituted amino or hydroxy, X is O, S, SO or SO2, ---Z represents -C, =C or -N, R1 and R2 independently represent hydrogen or alkyl (1-3C), Q is benzyl or 2-, 3- or 4-pyridylmethyl, wich groups may be substited with one or more more substituents from the group halogen, nitro, cyano, amino, mono- or di (1-3C)alkylamino, (1-3C) alkoxy, CF3, OCF3, SCF3, (1-4C)-alkyl, (1-3C)alkylsulfonyl or hydroxy, and salts and prodrugs thereof. It has been found that these compounds have interesting pharmacological properties due to a combination of (partial) agonism towards the members of the dopamine D2-receptor subfamily and affinity for relevant serotonin and/or noradrenergic receptors.

Abstract: A method of determining common three-dimensional structural features of protein surfaces is provided, as is use of representations of these common structures in molecular database searching and in designing focussed molecular libraries. The method is particularly concerned with the analysis and representation of protein surfaces such as b-turns, loops and contact surfaces. In one form, the method identifies common locations and orientations of amino acid side-chains, simplified as C?-C? vectors. In another form, the method identifies common regions of surface charge represented by grid points in three-dimensional space. Further provided are common three dimensional structural features of proteins that can be used to search molecular databases for the purposes of identifying molecules that match these common three dimensional structural features.

Abstract: A process of forming a capacitive audio transducer, preferably having an all-silicon monolithic construction that includes capacitive plates defined by doped single-crystal silicon layers. The capacitive plates are defined by etching the single-crystal silicon layers, and the capacitive gap therebetween is accurately established by wafer bonding, yielding a transducer that can be produced by high-volume manufacturing practices.

Abstract: A pressure sensor module is provided with an isolation platform which isolates stress. The pressure sensor module includes a base structure and a cantilever member formed in the base structure by an isolation gap. A pressure sensing element is located on the cantilever member such that the cantilever member provides stress isolation to the pressure sensing element.

Abstract: A convertible window system having two window sashes, a weatherstripping, and a tilt pivot assembly. The window system can be readily switched between single-hung and double-hung configuration. The weatherstripping assembly, which is operatively connected to each of the two sashes, has a number of regions. Each of these regions has different attributes which determine the types of translations and rotations that can be performed on a sash with a predetermined force. In a preferred embodiment, an upper sash can be removed from a window frame by the application of a predetermined force on the top of the sash while the sash is within a predetermined range of the weatherstripping assembly without the need for withdrawing guide pins from the channel of the weatherstripping assembly.