Abstract: A manufacturing method creates a type of telescope which is athermal, lightweight, optical quality for visible and IR applications. The method includes: a) optical mirrors being made by immersing a master, that is an optical component with a curvature opposite to the mirror required into an electrolytic bath where the applied current transfers metal ions and deposit them on the master, the cathode, as a layer, b) the layer being bonded by an adhesive, solder or any other attachment process to a mechanical reinforcing structure, c) after the hardening of the bond or glue, the thin layer being finally released from the master and having maintained the optical quality of the master. The master or mandrel can be cleaned and reused for repeating this method and manufacturing large series of telescopes.

Abstract: A process for forming an article having at least one precision surface is disclosed. The process includes providing a thin sheet in contact with a surface of a mandrel. The process then includes establishing a pressure differential between opposite sides of the thin sheet using a collapsible enclosure so that the thin sheet is drawn onto the mandrel surface, thereby causing the thin sheet to substantially conform to the shape of the mandrel surface. The shaped thin sheet is then secured to a support member to define the article. The article is then removed from the mandrel. The front surface of the thin sheet defines the precision surface of the article. A process for forming a dual-sided precision article is also disclosed, along with an adaptive optical system and method that employs the precision article.

Abstract: A method of controlling a combined plant to provide frequency support to a power grid operating at a variable grid frequency, wherein the combined plant includes at least one generator and an energy store, and the combined plant is adapted to supply power to the power grid, the method including the steps of charging the energy store at less than its rated power when frequency support is not needed. When frequency support is needed the combined plant is controlled to increase or decrease the overall power that it supplies to the power grid to provide frequency support. The control of the combined plant can be designed to maximize frequency support revenues.

Abstract: A process for forming an article having at least one precision surface is disclosed. The process includes providing a thin sheet in contact with a surface of a mandrel. The process then includes establishing a pressure differential between opposite sides of the thin sheet using a collapsible enclosure so that the thin sheet is drawn onto the mandrel surface, thereby causing the thin sheet to substantially conform to the shape of the mandrel surface. The shaped thin sheet is then secured to a support member to define the article. The article is then removed from the mandrel. The front surface of the thin sheet defines the precision surface of the article. A process for forming a dual-sided precision article is also disclosed, along with an adaptive optical system and method that employs the precision article.

Abstract: An offshore wind farm includes a plurality of wind turbines connected to an onshore converter station by means of a distributed power transmission system. The power transmission system includes a series of offshore converter platforms distributed within the wind farm. Each converter platform includes a busbar carrying an ac voltage for the converter platform and to which the wind turbines are connected. Each converter platform also includes one or more converter transformers connected to the busbar and a series of one or more converter modules. The power transmission system includes dc transmission lines which deliver generated power back to the onshore converter station.

Abstract: A wind turbine typically includes a generator and a rotating mechanical system having a natural period. The present invention relates to a method of controlling generator torque that minimizes oscillations in the speed of the generator rotor. In the event of a grid fault or transient, or a fault in the power converter, the generator torque is decreased at a substantially constant rate with respect to time. The rate at which the generator torque is decreases is proportional to the nominal rated torque of the generator and inversely proportional to an integer multiple of the natural period of the rotating mechanical system.

Abstract: A method of controlling a combined plant to provide frequency support to a power grid operating at a variable grid frequency, wherein the combined plant includes at least one generator and an energy store, and the combined plant is adapted to supply power to the power grid, the method including the steps of charging the energy store at less than its rated power when frequency support is not needed. When frequency support is needed the combined plant is controlled to increase or decrease the overall power that it supplies to the power grid to provide frequency support. The control of the combined plant can be designed to maximize frequency support revenues.

Abstract: An offshore wind farm includes a plurality of wind turbines connected to an onshore converter station by means of a distributed power transmission system. The power transmission system includes a series of offshore converter platforms distributed within the wind farm. Each converter platform includes a busbar carrying an ac voltage for the converter platform and to which the wind turbines are connected. Each converter platform also includes one or more converter transformers connected to the busbar and a series of one or more converter modules. The power transmission system includes dc transmission lines which deliver generated power back to the onshore converter station.

Abstract: A wind turbine typically includes a generator and a rotating mechanical system having a natural period. The present invention relates to a method of controlling generator torque that minimises oscillations in the speed of the generator rotor. In the event of a grid fault or transient, or a fault in the power converter, the generator torque is decreased at a substantially constant rate with respect to time as shown in graph (c). The rate at which the generator torque is decreases is proportional to the nominal rated torque of the generator and inversely proportional to an integer multiple of the natural period of the rotating mechanical system.

Abstract: A method for operating a user terminal to deliver advertising content to a user of the user terminal prior to the user commencing use of a software program on the user terminal is provided. The user terminal includes a processor and associated memory, a communications interface, and at least one output device. The method includes sending, via the communications interface, a service request to a software server, the service request including a request to use said software program; receiving, via the communications interface, a service response and an advertising reference from the software server; and delivering advertising content to the user through the at least one output device, the advertising content being derived from the advertising reference.

Abstract: A process for fabricating a metallic component is disclosed. The process includes performing multiple electroforming steps on an object to form metallic layers. The process includes performing between the electroforming steps masking and patterning steps using a non-conductive material. The resulting metallic component has either a single layer or multiple layers of cooling or heat transfer channels, which may be at right angles in adjacent layers. The non-conductive material can be removed during the process by a solvent or by melting. The object on which the metallic component is formed may be a flat or shaped mandrel from which the metallic component can be removed. The metallic component is particularly useful in forming optical components for use in extreme ultraviolet (EUV) systems and in cooling and heat transfer systems.

Abstract: Optical mirror elements for high bandwidth free space optical communication are produced by an electroforming replication technique. Onto the precision surface of a mandrel that is a negative of the required optical surface a layer of metal is deposited forming an exact copy of the mandrel surface and is then separated to form the required optical element. During the production process the mandrel may be coated with a variety of materials that are then separated together with the electroformed optical element during the release step to form a monolithic structure that includes a reflective coating. The mandrel remains unchanged by the process and can then be re-used. The high cost of conventional polishing techniques is therefore limited to the production of the mandrel. The replication process results in the production of low cost optical elements suitable for high bandwidth free space optical data transmission.

Abstract: A high-pressure pump for supplying internal combustion engines with fuel includes a housing, on which a timing unit for displacing the point of injection is accommodated. The timing unit includes an injection timing piston having inlet bores, and a regulating slide, whose face facing a cold-start accelerator piston has a prestress force applied to it, is movably accommodated in the injection timing piston. A spring element, which is applied directly to the injection timing piston, as well as a spring assembly, which is independent of the spring element and accommodated on a carrier and act on the regulating slide, are positioned between the cold-start accelerator piston and the opposing face of the injection timing piston.

Abstract: A high-pressure pump for supplying internal combustion engines with fuel includes a housing, on which a timing unit for displacing the point of injection is accommodated. The timing unit includes an injection timing piston having inlet bores, and a regulating slide, whose face facing a cold-start accelerator piston has a prestress force applied to it, is movably accommodated in the injection timing piston. A spring element, which is applied directly to the injection timing piston, as well as a spring assembly, which is independent of the spring element and accommodated on a carrier and act on the regulating slide, are positioned between the cold-start accelerator piston and the opposing face of the injection timing piston.