Abstract: The invention relates to a method, a server and a distributed system for configuring a network of CDN caching nodes. The network comprises a hierarchy of virtual CDN caching nodes collocated in a single layer of physical CDN caching nodes. Each physical CDN caching node runs a client-server application and at least one physical CDN caching node runs a server instance of the application. The server instance of the application is operative to detect a modification in the layer of physical CDN caching nodes and to receive traffic load information from the physical CDN caching nodes. The server instance is also operative to compute a new network configuration for the virtual CDN caching nodes based on the modification detected, the traffic load information received and locations of the physical CDN caching nodes and to configure the network of physical CDN caching nodes with the new network configuration.

Abstract: A power management and data center resource monitoring mechanism is provided for selecting new processing elements in a data center. When a condition is detected for selecting new processing elements, one or more processing elements are selected as the new processing elements based on at least a temperature parameter and a usage history parameter of at least some of the processing elements in the data center. Workload is consolidated onto the new processing elements to conserve energy.

Abstract: The invention relates to a method for managing the traffic load of a delivery node being in a state BLOCKED or UNBLOCKED. The method comprises the step determining that the traffic load of the delivery node is within a pair of upper and lower limits. The method also comprise the step of changing the state of the delivery node upon the determination that the traffic load of a delivery node is within the pair of upper and lower limits. Changing the state is changing from UNBLOCKED to BLOCKED or from BLOCKED to UNBLOCKED. The invention also relates to a delivery node suitable for implementing the method disclosed hereinabove.

Abstract: A rotor disc assembly 10 for an AC machine includes a rotor disc 20, permanent magnets 30 and a spider 40. The rotor disc 10 has a circumferential lip 22 projecting from a surface thereof. The permanent magnets 30 are positioned in a circular array on the surface of the rotor disc 20, with constant angular pitch, and so as to lie against the lip 22. The spider includes an annular base portion 41, with a plurality of arms 42 projecting radially outwards therefrom. The spider 40 is fixed to the surface of the rotor disc 20 such that each arm 42 is between and abuts a respective juxtaposed pair of the permanent magnets 30. The arms 42 and the members 30 are each provided with cooperating wedge-shaped cross sections such that each arm 42 constrains the respective two permanent magnets 30 both axially and tangentially on the surface of the rotor disc 20.

Abstract: A generating set includes an engie driven generator (PGM) having two sets of stator windings (Ga and Gb). A bi-directional AC/DC converter (BCo) has its AC input connected to a junction between the two sets of stator windings (Ga and Gb) and its DC input connected to a number of the generator (PGM) is converted into an intermediate DC link by a convertor (Col) to produce an output for a load Lo. In normal operation of the system, an emf generated in one (Ga) of the sets of stator windings is rectified by the bi-direcitonal converter (BCo) to charge the energy storages (ESI-ESN) whilst the remainder of the generator output is fed through the converter to the load (Lo). In the event of a stepped increase in the load demand, the bi-directional converter (BCo) is operated to feed energy from the storage devices (ESI-ESN) to the stator windings (Ga) of the generator (PGM) to impart a driving torque to the generator rotor to accelerte the rotor to meet the increased load demand.

Abstract: A toroidal AC generator includes an outer casing and an annular stator core of ferromagnetic material which is encased in a hollow annular cover of plastics material and which is fixed to the casing between the discs of a twin disc rotor. Each rotor disc carries a circular array of alternately polarised permanent magnets which face the stator core. The hollow annular cover is a two-part moulding and is formed of radially inner and outer ring portions which are joined by circular arrays of radial ribs which extend across the opposed radial faces of the annular core and form open-ended radial passages for the electrical phase windings which are wound around the cover. The ribs project radially beyond the radially outer ring portion and form hooks around which a winding may be retained temporarily during winding.

Abstract: A generating set includes an engie driven generator (PGM) having two sets of stator windings (Ga and Gb). A bi-directional AC/DC converter (BCo) has its AC input connected to a junction between the two sets of stator windings (Ga and Gb) and its DC input connected to a number of the generator (PGM) is converted into an intermediate DC link by a convertor (Col) to produce an output for a load Lo. In normal operation of the system, an emf generated in one (Ga) of the sets of stator windings is rectified by the bi-direcitonal converter (BCo) to charge the energy storages (ESI-ESN) whilst the remainder of the generator output is fed through the converter to the load (Lo). In the event of a stepped increase in the load demand, the bidirectional converter (BCo) is operated to feed energy from the storage devices (ESI-ESN) to the stator windings (Ga) of the generator (PGM) to impart a driving torque to the generator rotor to accelerte the rotor to meet the increased load demand.

Abstract: An electric power generating set which automatically varies its speed to match load variations at any time includes an engine driven generator G which provides a positive, Ga and a negative, Gb AC output voltage each of which is rectified by a respective rectifier Re3a, Re3b. Each rectifier Re3a,Re3b has one terminal connected to a common neutral line N. The DC output voltage of each rectifier Re3a, Re3b is boosted in a respective booster circuit which also has one terminal connected to the neutral line N. The combined output of the two booster circuits, Va+Vb is fed to an Inverter IN which converts it to the AC power output of the generating set. A DC load current between the booster circuits and the inverter IN is monitored and used to provide a speed demand feedback signal Srs to the speed control of the engine EN.

Abstract: A toroidal AC generator includes an outer casing (11) and an annular stator core (33) of ferromagnetic material which is encased in a hollow annular cover (34) of plastics material and which is fixed to the casing (11) between the discs (14 and 15) of a twin disc rotor (10). Each rotor disc (14, 15) carries a circular array of alternately polarised permanent magnets (23 and 24) which face the stator core (33). The hollow annular cover (34) is a two-part moulding and is formed of radially inner and outer ring portions which are joined by circular arrays of radial ribs which extend across the opposed radial faces of the annular core (33) and form open-ended radial passages for the electrical phase windings which are wound around the cover (34). The ribs project radially beyond the radially outer ring portion and form hooks around which a winding may be retained temporarily during winding.

Abstract: A rotor disc assembly (10) for an AC machine includes a rotor disc (20), permanent magnets (30) and a spider (40). The rotor disc (10) has a circumferential lip (22) projecting from a surface thereof. The permanent magnets (30) are positioned in a circular array on the surface of the rotor disc (20), with constant angular pitch, and so as to lie against the lip (22). The spider includes an annular base portion (41), with a plurality of arms (42) projecting radially outwards therefrom. The spider (40) is fixed to the surface of the rotor disc (20) such that each arm (42) is between and abuts a respective juxtaposed pair of the permanent magnets (30). The arms (42) and the members (30) are each provided with cooperating wedge-shaped cross sections such that each arm (42) constrains the respective two permanent magnets (30) both axially and tangentially on the surface of the rotor disc (20).

Abstract: An electric power generating set which automatically varies its speed to match load variations at any time includes an engine driven generator G which provides a positive, Ga and a negative, Gb AC output voltage each of which is rectified by a respective rectifier Re3a, Re3b. Each rectifier Re3a,Re3b has one terminal connected to a common neutral line N. The DC output voltage of each rectifier Re3a, Re3b is boosted in a respective booster circuit which also has one terminal connected to the neutral line N. The combined output of the two booster circuits, Va+Vb is fed to an Inverter IN which converts it to the AC power output of the generating set. A DC load current between the booster circuits and the inverter IN is monitored and used to provide a speed demand feedback signal Srs to the speed control of the engine EN.

Abstract: A generator or a 3-phase motor is arranged to provide multipolar permanent magnet excitation in combination with multipolar reluctance distribution wherein different numbers of poles are used for the permanent magnet excitation and for the reluctance distribution so that the principal working flux has a finite waveform. An annular rotor rotates about a cruciform stator. The magnets are buried in pole pieces of the stator so they converge radially inwardly with a triangular pole piece between them. Each pole piece is joined to the remainder of the stator by a bridge piece. The inner periphery of the rotor is formed as a circumferential array of teeth separated by recesses. The rotor may be within an annular stator or the machine may be linear.

Abstract: An AC generator comprises a rotor 25 within a stator 24. The rotor carries a fan 27 at one end of the stator. The fan 27 is within a casing 30 which forms volute discharge passages 32. The fan 27 has blades 31 which project from the hub 28 at an angle which is oblique to the radial whereby those blades 31 trail the radial. The stator windings 23 form terminal leads 34 which are led from the end of the stator 24 remote from the fan 27. A circumferential array of cleats 35 which each have the form of a comb, support and guide the terminal leads 34 circumferentially, spaced from one another, to a certain location at the top from which the leads are taken and connected to terminals above. Those terminals are formed by the lower ends of busbars (56 to 58, 61 to 69) which extend through and which are supported by a structural panel of insulating material which forms an insulating barrier between the ends of those busbars.