Abstract: Rotors for electrical machines and methods of fabricating the same are disclosed. Electrical machine rotors may include a hollow non-magnetic shaft, an active region, and a plurality of coolant passages extending within the active region. The hollow non-magnetic shaft may extend along an axis and have an exterior surface that defines a shaft space extending along the axis. At least a portion of the active region may be disposed within the shaft space.

Abstract: A power line protection system and method are described with a current meter for monitoring the current in the protected power line and a circuit breaker, with the current meter including a sensor, particularly a fiber optic current sensor, for monitoring a direct current component in the current transmitted and an analyzer for testing the direct current component and for generating a fault signal for the circuit breaker.

Abstract: Rotating machines and rotors therefor are disclosed. The bearings may be magnetic bearings configured to magnetically levitate the rotor. The rotors may include a hollow fiber-reinforced composite shaft and a magnetic bearing rotor core disposed on the shaft and configured for use with the magnetic bearing. In some examples, the rotating machines may be electrical machines.

Abstract: A method and control system are disclosed for optimizing load scheduling for a power plant having one or more generation units. The method can include analyzing the operating state of one or more components of generation units in terms of one or more risk indices associated with one or more components of generation units; updating an objective function that reflects the state of one or more components of generation units; solving the objective function to optimize a schedule of the one or more generation units and operating state of one or more components of generation units; and operating the one or more generation units at optimized schedule and operating state.

Abstract: A method of controlling fluid flow in a fluid network system by fluid machines includes obtaining a respective current flow rate associated with each fluid machine, obtaining a current fluid machine speed of each fluid machine, obtaining desired flow rates in the system, and determining a new fluid machine speed for each fluid machine based on the current fluid machine speed and a change in the fluid machine speed required to obtain the desired flow rates. The change in fluid machine speed is determined by minimizing a total fluid machine power which is a function dependent of the change in the fluid machine speed, the minimization being performed with constraints for flow rate, fluid machine pressure and fluid machine speed. The method include controlling the speed of the fluid machines according to the new fluid machine speeds such that the minimum total fluid machine power in the system is attained.

Abstract: Fault analysis for an electric network having a plurality of multi-phase buses is performed by computing equivalent circuits for the multi-phase buses of interest. Each equivalent circuit includes an N×N impedance matrix, N corresponding to the number of phases of the multi-phase bus for which that equivalent circuit is computed. Elements of the impedance matrices are determined based on voltages resulting from a plurality of experimental current injection vectors and a factorized pre-fault admittance matrix. The pre-fault admittance matrix represents nodal admittance of the multi-phase buses without faults. A fault current injection vector for each multi-phase bus and fault type of interest is determined based on the equivalent circuit determined for that multi-phase bus. A fault voltage vector for each multi-phase bus and fault type of interest is determined based on the factorized pre-fault admittance matrix and the fault current injection vector determined for that multi-phase bus and fault type.

Abstract: A thermosyphon heat exchanger includes a plurality of first conduit elements and a plurality of second conduit elements. Each first conduit element has a heat absorbing portion defining a first plane and a first fluid transfer portion defining a second plane. The first plane and the second plane are twisted relative to each other. Each second conduit element has a heat releasing portion and a second fluid transfer portion or a connection to a fluid return line. At least one first conduit element and at least one second conduit element are connected to each other such that the fluid in the thermosyphon heat exchanger can flow in a closed loop through said first conduit element and said second conduit element.

Abstract: A transformer arrangement and transformer for mitigating transient voltage oscillations. The transformer included a transformer core enclosing at least one core leg. A winding is wound around one of the at least one core leg. The winding extends from a first winding terminal to a second winding terminal and includes a first winding section along a first conductor extending from the first winding terminal to a first intermediate end point, and a second winding section along a second conductor extending from a second intermediate end point to the second winding terminal. The transformer arrangement further includes an external passive electric component connected between the first intermediate end point and either the second intermediate end point or the second winding terminal arranged to decrease an effective difference between capacitive and inductive voltage distributions between the intermediate end points such that transient voltage oscillations in the winding are mitigated.

Abstract: Graphical tool and method for designing device-to-device configurations used in power systems. The tool comprises software program instructions configured to allow a user to graphically associate on a monitor an intelligent electronic device (IED) selected from an available list to a corresponding switching device of the power system. For a first IED associated to corresponding switching device, the user graphically configures on the monitor a related logic by selecting one or more logical inputs/outputs and one or more target IEDs from/to which said logical inputs/outputs are to be received/sent, respectively.

Abstract: A method for communication between a wireless device node in a wireless sensor network (WSN) and control apparatus or control processes of an industrial control system is used to determine a method of radio transmission which provides a greater or a lesser measure of transmission quality between nodes. Thus a transmitter node measures a transmission quality metric of at least one packet received from two or more different switching branches, identifies which of the two or more switching branches has the greater transmission quality metric, distributes data packets with a first priority to the switching branch with the greater transmission quality metric, and transmits data packets with the first priority such as real-time data on the switching branch with the greater transmission quality metric. A wireless node, a sensor network system and a computer program for carrying out the method are described.

Abstract: A system and method are provided for storing electric energy in the form of thermal energy. A thermoelectric energy storage system includes a working fluid circuit for circulating a working fluid through a heat exchanger, and a thermal storage medium circuit for circulating a thermal storage medium. The thermal storage medium circuit includes at least one hot storage tank, an intermediate temperature storage tank, and a cold storage tank connected together via the heat exchanger. A proportion of the storage medium is redirected to or from the intermediate storage tank from or to the hot or cold storage tank, joining another proportion which flows directly between the cold and hot storage tank.

Abstract: One or more techniques and/or systems are provided for parsing tabular data of a document. That is, a document may comprise arbitrarily formatted content (e.g., an equipment inspection report generated by an engineer). Respective rows of the document may be clustered into one or more row clusters based upon row proximity and/or numeric content (e.g., rows having similar numeric content may comprise logically related information). One or more vertical clusters may be generated within respective row clusters based upon vertical overlap. In this way, row clusters and/or vertical clusters may be searched for one or more values that may be assigned to a search term. For example, a row cluster may comprise a search term “Average temp”. One or more vertical clusters within the row cluster may be searched for a word that matches a pattern criteria (e.g., a two digit number), which may be assigned to the search term.

Abstract: An exemplary heat exchanger is configured for removing heat energy from a heat generator. The heat exchanger including at least one conduit for a working fluid, which is arranged in an upright position of at least 45°, each conduit having an exterior wall and at least one interior wall for forming at least one evaporator channel and at least one condenser channel within the conduit. Furthermore, the heat exchanger includes a first heat transfer element for transferring heat into the evaporator channel and a second heat transfer element for transferring heat out of the condenser channel.

Abstract: Method of protecting a distribution network with a line interconnecting busbars, each busbar being connectable, by means of switching devices adjacent to the busbar, to the line and to loads and/or generators. The method divides the distribution network in multiple protection areas, each comprises a busbar, a protection device and an area controller. Upon a change in connect status of a distribution feeder line, load or generator connectable to one of the busbar, the logic controller in this protection area re-calculates the short circuit level of the areas. Based on the recalculated short circuit levels, the protection settings of the areas may be adapted. The embodiment also provides a system and computer program product adapted to perform the method.

Abstract: A network management agent, device or module determine the network topology of a communication network based on at least one neighbor network or end device identity and corresponding network link communication delay collected from, determined by, and stored in a Management Information Base of, at least one first network device of the communication network. Neighbor identities and communication delays are determined according to the IEEE 1588 standard.

Abstract: According to one aspect of the teachings herein, a system for obtaining electricity from wind turbines provides advantageous operation with respect to offshore wind turbines where the size and weight of electricity generation and collection equipment are key considerations. The contemplated system includes an apparatus that is configured for collecting wind-generated electricity at a fixed low frequency and at a desired collection voltage, based on the advantageous configuration and use of a modular multilevel converter or MMC.

Abstract: The subject matter described herein includes a magnetic bearing assembly and an arrangement of position sensors for the magnetic bearing assembly. In one example the magnetic bearing assembly includes a rotor for fixedly coupling to a shaft for rotating with the shaft. The assembly further includes at least one stator assembly located adjacent to the rotor and circumferentially surrounding the shaft. The stator assembly includes a control coil for magnetically supporting the rotor. The stator assembly further includes a plurality of position sensors that are circumferentially spaced from each other and that extend radially from the stator assembly for measuring an indication of axial displacement of the rotor.

Abstract: Exemplary methods and systems visualize or contour a power distribution system state by displaying to an operator output data values interpolated at output data locations from input data including distributed input data sensor locations in three dimensions and corresponding dynamically updated input data values. The method includes defining triangles in the volume, and determining, for each triangle, closest input data locations according to a closeness criteria. The method also includes projecting each triangle onto a visualization plane, and determining, for an output data location on the visualization plane at least one triangle, the projection of which includes the output data location. The method interpolates, for the output data location, the input data values of the closest input data locations of each of the at least one determined triangle to generate an output data value corresponding to the output data location.

Abstract: A method, item communication arrangement and a computer program product communicate items representing process control objects to a user of a wireless terminal in a process control system. The arrangement includes an item communication control unit providing the items representing process control objects and configured to continuously determine weights of the items and visually communicate items to the user via the wireless terminal in an order defined by the weights of the items. The weight of an item is determined based on an item selection pattern of the user.

Abstract: A rotor for a synchronous reluctance machine wherein a torque ripple behaviour of the machine is optimized by altering the geometry of insulating barriers of the rotor. A q-axis pitch angle is used as a design variable instead of setting its value equal to the rest of the rotor slot pitches or binding its value to the stator slot pitch. The resulting rotor has a non-regular slot pitch across the q-axis and substantially regular slot pitch otherwise. Synchronous reluctance machines that employ rotor discs and rotor assemblies in accordance with the present invention may exhibit low torque ripple without sacrificing high torque values.