Abstract: A method for primary regulation of a combined gas and steam turbine installation in network operation, wherein the combined gas and steam turbine installation includes a gas turbine and a steam turbine arranged along at least one shaft includes operating at least one steam turbine actuating valve on a restricted basis along a working steam supply line to at least one pressure stage of the steam turbine so as to provide a steady-state steam turbine reserve power, wherein the at least one steam turbine actuating valve is changed to a less restricted state if a network frequency decreases so as to require network frequency support.

Abstract: A gas turbine generator set includes a compressor unit including at least one compressor, at least one generator and at least one combustion chamber. Exhaust gases from at least one turbine are recirculated for a further thermal utilization. At least one cooling fluid compressor is configured to compress a cooling fluid including at least one of fresh air and a portion of the recirculated exhaust gases for a cooling of thermally loaded parts.

Abstract: A multilevel voltage source converter for high voltage DC power transmission and reactive power compensation. The voltage source converter includes at least one phase element including a plurality of semiconductor switches to interconnect a DC voltage and an AC voltage. The voltage source converter also includes at least one auxiliary converter to act as a waveform synthesizer to modify the DC voltage presented to the DC side of the phase element.

Abstract: A current sensor for measuring current through a conductor with the current sensor including a cable looped around the conductor to be monitored, and a transformer winding disposed in the cable for measuring current flow based on the Rogowski principle. The cable has opposite end portions coupled in an abutting relationship to form an endless loop with the winding flush with opposite end faces of the opposite and portions of the cable. The current sensor also has a coupling in the form of a sleeve including an assembly for attaching and detaching the opposite end positions of the cable having a stop ring which grips one of the end portions and a push button which is selectively movable against the stop ring for releasing the grip to open the opposite end portions. The cable may have a temperature sensor and a memory in which the measurement characteristics of the sensor are held. The sensor is reliable and accurate, and it can be left permanently in an electrical apparatus, or replaced, with no difficulty.

Abstract: Methods and systems for the removal of SO2 from waste combustion flue gas are described herein. One such system for removing SO2 from waste combustion flue gas containing SO2 uses a semi-dry desulfurization system for contacting the flue gas with a solvent moistened absorption material. Thereafter, a recirculated water quench is used for contacting the flue gas with recirculated water at a relatively low pH, followed by a condenser used for contacting the flue gas with a water spray. Additionally, a NaOH supply for supplying NaOH to the condenser and an oxidizing catalyst supply for supplying an oxidizing catalyst to the condenser, are likewise used to produce cleaned flue gas for release to the atmosphere.

Abstract: A turbine diaphragm has radially inner and outer hollow diaphragm rings (22, 24) comprising box structures that include the radially inner and outer platform portions (261, 262) of static blade units (26) as part of their structures. The box structures are strengthened by the incorporation of ribs or struts (28, 30) which extend radially and axially between the walls of the box structures.

Abstract: A method for combustion of a fuel and treatment of the resulting flue gas includes: combusting a fuel to produce a hot flue gas stream containing at least carbon dioxide (CO2) and sulfur dioxide (SO2), bringing the flue gas stream into contact with solid calcium oxide (CaO) in a carbonation reactor operating at a temperature at which CO2 in the flue gas reacts with CaO to form solid calcium carbonate (CaCO3), heating CaCO3 in a calcination reactor operating at a temperature at which CaCO3 is converted to CaO and CO2, and recirculating CaO formed in the calcination reactor back to the carbonation reactor. Heating can be at least partially effected by indirect heat exchange with hot flue gas from the combustion. Flue gas used for the indirect heat exchange can be subsequently subjected to dry desulfurization before it is brought into contact with CaO in the carbonation reactor.

Abstract: An electric generator (1) includes a casing (2) that envelops a stator (3) and a rotor (4). The casing (2) has an aperture (5) through which the generator casing inside (7) is inspectable during generator operation. A method includes inspecting during generator operation, through the aperture (5) of the casing (2), the casing inside (7).

Abstract: A device for detecting and locating at least one electric discharge in equipment insulated by fluid contained in an electrically-conductive housing. The equipment includes a plurality of grounding lines connected between the housing and ground. The device includes a plurality of Rogowski coil type current detectors and a mechanism synchronously comparing signals delivered by the current detectors. The coil of each detector is placed around a respective one of the lines. Each detector delivers a signal representative of current flowing in the line, with occurrence of an electric discharge giving rise to a sudden variation in the current, and with electric discharge being located within an inside zone of the housing situated in proximity of the line that is surrounded by the detector that was first to deliver the sudden variation of current.

Abstract: A power electronic converter for use in high voltage direct current power transmission and reactive power compensation comprises three converter limbs, each converter limb including first and second DC terminals for connection in use to a DC network and an AC terminal for connection in use to a respective phase of a three-phase AC network, each converter limb defining first and second limb portions being connected in series between the respective AC terminal and a respective one of the first and second DC terminals, each limb portion including at least one switching element being controllable in use to facilitate power conversion between the AC and DC networks, the power electronic converter further including a plurality of auxiliary units, each auxiliary unit being operably associated with the respective phase of the AC network, each auxiliary unit including at least one module including a voltage source, the limb portions being controllable in use to define at least one three-phase static synchronous compen

Abstract: A voltage source converter is used in high voltage direct current power transmission and reactive power compensation. The voltage source converter includes first and second DC terminals for connection in use to a DC network, three phase elements and at least one auxiliary converter connected between the first and second DC terminals, each phase element including a plurality of primary switching elements and at least one AC terminal for connection in use to a respective phase of a multi-phase AC network, the plurality of primary switching elements being controllable in use to facilitate power conversion between the AC and DC networks, the or each auxiliary converter being operable in use to act as a waveform synthesizer to modify a first DC voltage presented to the DC network so as to minimize ripple in the DC voltage.

Abstract: The present invention relates to methods and systems for improving the utilization of energy in a cement manufacturing plant comprising an absorption based contaminant, e.g. CO2, capture process using thermal regeneration of a liquid absorbent. The methods and systems of the present invention are characterized in that the thermal regeneration of the liquid absorbent is at least partially effected using a hot exhaust gas stream generated in the kiln of the cement manufacturing plant.

Abstract: Shroud device thermally protecting a gas turbine blade, having a ceramic layer and a metallic layer, the metallic layer being thermally protected by the ceramic layer, the ceramic layer being mechanically joined to the metallic layer by a fixation device having a plurality of protrusions located in the metallic layer designed so as to engage with a plurality of cavities located in the ceramic layer, such that there exists a gap between the cavities and the protrusions at ambient temperature, the gap disappearing at high temperature operation of the gas turbine, the protrusions being then locked into the cavities.

Abstract: The arrangement of an electric machine, a connecting system and a converter, includes the connecting system connected between the electric machine and the converter. The connecting system has an enclosure that houses non-shielded conductors each non-shielded conductor is connected between a phase of the electric machine and the inner side of the converter. The non-shielded conductors of the connecting system that are connected to an operating phase of the electric machine are adjacent to conductors of the connecting system that are not connected to operating phases of the electric machine.

Abstract: A voltage source converter comprising three phase elements defining a star connection in which a first end of each phase element is connected to a common junction; at least two converter limbs, each converter limb including first and second DC terminals for connection in use to a DC network and an AC terminal connected in series with a second end of a phase element, each converter limb defining first and second limb portions, including a chain-link converter, each chain-link converter including chain-link modules; and a third DC terminal connected to the common junction of the star connection to define an auxiliary connection, wherein in use a current is injected into the auxiliary connection to modify a voltage of each chain-link module in each limb portion.

Abstract: A DC voltage source converter for use in high voltage DC power transmission comprising at least one chain-link converter connected between first and second DC terminals. The or each chain-link converter includes a chain of modules connected in series and each module including at least one pair of semiconductor switches connected in parallel with an energy storage device. The or each chain-link converter is operable when DC networks are connected to the first and second DC terminals to control switching of the modules to selectively charge or discharge the energy storage device of one or more of the modules, as required, to offset any difference in the DC voltage levels of the DC networks.

Abstract: A power electronic converter (30)is for use in high voltage direct current power transmission and reactive power compensation, the power electronic converter (30) including three phase elements (32) defining a star connection (36) and a converter unit (34) including first and second DC terminals (50,52) for connection in use to a DC network (56) and three AC terminals (54), the converter unit (34) including a plurality of switching elements (70,74) controllable in use to facilitate power conversion between the AC and DC networks (44,56), the power electronic converter (30) further including a third DC terminal (78) connected between the first and second DC terminals (50,52), the third DC terminal (78) being connected to a common junction (40) of the star connection (36) to define an auxiliary connection (82), the auxiliary connection (82) including at least one dump resistor (84) connected between the common junction (40) and the third DC terminal (78), wherein the switching elements (70,74) of the converter

Abstract: Disclosed herein is a system comprising an evaporator; a water reservoir in fluid communication with the evaporator; the water reservoir being located upstream of the evaporator; and a first steam drum in fluid communication with the evaporator; the first steam drum being located downstream of the evaporator; where the water reservoir is operative to supply feedwater to the evaporator while maintaining a predetermined water level in the first steam drum.

Abstract: A cooling system for bushings of an electric generator, which includes a casing housing a stator and a rotor connected to a rotor shaft activating at least a fan defining at least a high pressure zone and a low pressure zone. The generator has a plurality of phases electrically connected to hollow phase rings that are electrically connected to bushings supported by the casing and having cooling circuits to let a cooling medium pass through them to cool them. The outlets of the bushing cooling circuits are housed in the high pressure zone and are connected to inlets of the hollow phase rings. A method for cooling the bushings of an electric generator is also provided.

Abstract: The burner (1) for a gas turbine includes a duct (2) housing a plurality of tetrahedron shaped vortex generators (3) and a lance (4) to inject a fuel to be combusted. Within the duct (2), a plurality of vortex generators (3) are provided with a plurality of holes (9) for injecting cooling air. The cooling holes (9) define passing through areas that are non-uniformly distributed on a top wall (11) of the vortex generators (3). A method for locally cooling a hot gases flow passing through a burner includes non-uniformly injecting cooling air from a vortex generator into the hot gas flow in the duct, which can reduce the occurrence of flashback in the burner.