Patents Assigned to Asea Brown Boveri AG
  • Patent number: 6173790
    Abstract: A process and a device for atomization of a liquid extinguishing medium, in which the liquid extinguishing medium and a liquid inert gas are mixed in a mixing unit to form a liquid extinguishing medium mixture. The mixture is conveyed through a conduit to a distributing device such as extinguishing nozzles. As the mixture exits the distributing device the mixture is atomized, forming an aerosol spray for extinguishing a fire within an extinguishing area defined by the aerosol spray. A detector arranged in the extinguishing area for detection of parameters relating to extinguishing of the fire is connected to an evaluation device which in turn is connected to a control valve. The control valve regulates the quantity of liquid inert gas supplied to the mixing unit.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: January 16, 2001
    Assignees: Minimax GmbH, ASEA Brown Boveri AG
    Inventors: Manfred Russwurm, Frederic Aebischer
  • Patent number: 6167690
    Abstract: In a control system for controlling at least one variable (TITm) of a process, the at least one variable (TITm) being calculated from a multiplicity of measured process variables (TATm, pCm), the measured process variables (TATm, pCm) in each case being measured via associated measuring sections (18, 19), the transfer functions (G2(s), G1(s)) of which have a different time response, an improvement in particular during transient actions is achieved in that, to avoid instability, correction means (21) which equalize the different time responses of the individual measuring sections (18, 19) are provided.
    Type: Grant
    Filed: July 7, 1998
    Date of Patent: January 2, 2001
    Assignee: Asea Brown Boveri AG
    Inventors: Stephan Hepner, Andrew Wihler
  • Patent number: 6168380
    Abstract: In a cooling system for the leading-edge region of a hollow gas-turbine blade, a duct (10) extends inside the thickened blade leading edge (5) from the blade root (1) up to the blade tip (2). The duct (10), via a plurality of bores (9) made in the blade leading edge, communicates with a main duct (3), through which the cooling medium flows longitudinally, and the flow through the duct (10) occurs longitudinally over the blade height, and the duct (10) is formed with a variable cross section. The cross section of the duct (10) increases continuously in the direction of flow of the cooling medium from the blade root up to the blade tip. In the case of blades having a cover plate (11), the duct (10) merges at its top end into a chamber (12), which is mounted below the cover plate and is in operative connection with a pressure source, the pressure of which is lower than the pressure in the main duct.
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: January 2, 2001
    Assignee: Asea Brown Boveri AG
    Inventor: Bernhard Weigand
  • Patent number: 6169676
    Abstract: An invertor having a plurality of invertor bridges which operate in parallel and whose output voltages are summed. The invertor bridges are driven with pulse duration modulation according to an auxiliary control voltage. The auxiliary control voltages of the individual invertor bridges have a constant phase difference between one another. The output voltages of the bridges are summed by a center tap which is grounded by a ground connection. Effective suppression of the common-mode current distortion is achieved by having the switch arranged in the ground connection.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: January 2, 2001
    Assignee: Asea Brown Boveri AG
    Inventors: Peter D{umlaut over (a)}hler, Osvin Gaupp, Gerhard Linhofer, Jean-François Ravot
  • Patent number: 6168875
    Abstract: An iridium-niobium alloy bond coat is used under a ceramic thermal barrier coating on turbine blades and vanes to improve the life of the thermal barrier coating. Between the bond coat and the substrate is an underlying protective coating which is either a low pressure plasma sprayed coating such as a NiCoCrAlY alloy or a vapor deposited coating such as tantalum, nickel-tantalum or rhenium. Heat treatment and preoxidation procedures may be used to form the desirable bonds and materials.
    Type: Grant
    Filed: October 2, 1998
    Date of Patent: January 2, 2001
    Assignee: Asea Brown Boveri AG
    Inventors: Michael Cybulsky, Thomas B. Gibbons
  • Patent number: 6164655
    Abstract: The object of the invention is to provide an improved method for sealing off the separating gap, formed between a rotor and a stator, in a non-contacting manner, with which method the service life of the components involved can be increased. In addition, an arrangement for carrying out the method is to be shown. According to the invention, this is achieved in that the flow layers (35, 36), having different circumferential velocities, of the working fluid (18) are divided after the choking action into a first partial flow (35') having a high circumferential velocity and a second partial flow (36') having a low circumferential velocity, the first partial flow (35') is merely deflected, only the second partial flow (36') is swirled and is finally directed parallel to the deflected first partial flow (35') into the latter. To this end, the opposing surface (24) of the choke point (22) is designed as a flow divider for the working fluid (18).
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: December 26, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Mihajlo Bothien, Joachim Bremer, Jurg Greber, Markus Loos, Ulf Christian Muller, Dirk Wunderwald
  • Patent number: 6165848
    Abstract: The invention relates to a method for the production of a MOS-controlled power semiconductor component (30), which power semiconductor component (30) comprises, in a common substrate (31), a plurality of component cells which are arranged next to one another and are connected in parallel. A bipolar transistor formed by a collector region (33) of a first conductivity type, a superior base region (32) of a second conductivity type and an emitter region (37) of the first conductivity type, which emitter region is incorporated from above into the base region (32), is present in each component cell (59).
    Type: Grant
    Filed: November 28, 1997
    Date of Patent: December 26, 2000
    Assignee: Asea Brown Boveri AG
    Inventor: Uwe Thiemann
  • Patent number: 6166456
    Abstract: The invention specifies a disconnector for decoupling a load from a supplying AC voltage network. The disconnector comprises at least one disconnector stage having a series circuit comprising at least two reverse-conducting gate turn-off thyristors which are connected cathode to cathode. The gate turn-off thyristors are preferably hard driven. This allows the use of a single circuit capacitor in parallel with the series-connected gate turn-off thyristors. This embodiment has the advantage that, during disconnection, the current commutates early from the gate turn-off thyristors, which means that the disconnection capacity can be increased.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: December 26, 2000
    Assignee: Asea Brown Boveri AG
    Inventor: Horst Gruning
  • Patent number: 6162018
    Abstract: The invention relates to a rotor for thermal turbomachines in a steam power process with a centrally arranged hollow space, several axis-symmetrical hollow spaces, at least two pipes with different diameters and lengths, and at least two through-openings in the mantle, whereby at least one opening is arranged in the turbine part and at least one opening in the compressor part or the middle part, and the openings of the various pipes overlap in the warm operating state in the turbine part, while they overlap in the compressor part and middle part in the cold operating state. At the waste gas side end of the rotor, the hollow space is in the cylindrical part limited by the inside wall of the through-pipe and is provided for supplying steam. The pipe is surrounded in the cylindrical part by another hollow space that is arranged concentrically around the pipe and is provided for removing steam.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: December 19, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Alexander Beeck, Cornelis Striezenou
  • Patent number: 6161385
    Abstract: A turbomachine, in particular a gas turbine, is in the traditional manner provided with air cooling of the components that are subject to a high thermal stress. The cooling system (21, 31, 41) is provided with elements through which another medium (25, 35, 45), for example water or steam, can be added to the cooling system during peak demand. This medium displaces cooling air (26, 36, 46) from the cooling system, the air being then available additionally in a heat generator (2, 4). This means that more fuel (12, 13) can be added without increasing the hot gas temperature (T.sub.1, T.sub.3) at the turbine inlet (301, 501), and the power is increased. The quantity of the medium added to the cooling system is controlled by control elements (24, 34, 44) as a function of a control deviation (P.sub.set -P.sub.act) of the power.
    Type: Grant
    Filed: October 19, 1999
    Date of Patent: December 19, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Dieter Rebhan, Jost Braun, Thomas Zierer, Stefan Rofka
  • Patent number: 6159830
    Abstract: In a process for adjusting the carrier lifetime in a semiconductor component (1) by means of particle irradiation (P), at least two defect regions (10, 11, 12, 13) are produced in the semiconductor component (1). In this process, a particle beam (P), consisting of particles (a, b, c, d) with at least approximately the same initial energy, is acted on by at least one means (2), before reaching the semiconductor component (1), in such a way that the particles (a, b, c, d) subsequently have different energy values, at least two energy value groups being distinguishable. It is thereby possible, with a single particle irradiation operation, to produce an arbitrary number of defect regions whose arrangement and weighting is arbitrarily selectable.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: December 12, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Norbert Galster, Pavel Hazdra, Jan Vobecky
  • Patent number: 6160442
    Abstract: In a load-side filter of an n-phase converter circuit arrangement, the capacitors are arranged in at least two n-phase capacitor groups, one of which is hard-grounded and the other of which is grounded with a high impedance via a grounding resistor.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: December 12, 2000
    Assignee: Asea Brown Boveri AG
    Inventor: Gerhard Wild
  • Patent number: 6155720
    Abstract: The invention relates to a journal bearing for the shafts of high-speed rotors, and provides simple, and therefore low-cost, centering of squeeze film dampers for high-speed rotors, with improved long-term behavior, less installation space requirements and adequate concentricity accuracy. A centering element divides the annular gap into two partial annular gaps, with the bearing housing being configured in at least two parts and with a first bearing housing part bounding the first partial annular gap radially toward the outside and a second bearing housing part bounding the second partial annular gap radially toward the outside.
    Type: Grant
    Filed: July 26, 1999
    Date of Patent: December 5, 2000
    Assignee: Asea Brown Boveri AG
    Inventor: Josef Battig
  • Patent number: 6155054
    Abstract: The steam generator (1) includes at least an evaporator (8), a low-pressure drum (10), a separator (13) and a blowdown tank (22). A recirculation line (16) extends from the separator (13) to the low-pressure drum (10). A line (12) with a feed unit (11) extends from the low-pressure drum (10) to the evaporator (8). The feed unit (11) is designed for a capacity which is larger than the capacity of normal full-load operation of the steam generator (1). The separator (13) communicates via two differing line sections (18, 20) with the blowdown tank (22). One line section (18) is designed for a large mass flow at a small pressure difference between the separator (13) and the blowdown tank (22). The other line section (20) is designed for a small mass flow at a high pressure difference between separator (13) and blowdown tank (22).
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: December 5, 2000
    Assignee: Asea Brown Boveri AG
    Inventor: Erhard Liebig
  • Patent number: 6152726
    Abstract: A burner for operating a heat generator includes a rotation generator (100) for a combustion air stream (115), a device for injecting at least one fuel (112, 116) into the combustion air stream, a number of transition channels (201) for transferring a flow formed in the rotation generator into a mixing pipe (20) located downstream from these transition channels, and a pilot burner system (300) in the lower part of the mixing pipe (20), in which the pilot burner system (300) is in active connection with rotation generators (400) located at the end side of the mixing pipe (20). The interaction between the pilot burner system and rotation generators ensures maximized flame stability in the combustion chamber (30), and a general minimization of pollutant emissions, while increasing the load range for lower pollutants towards smaller loads.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: November 28, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Thomas Ruck, Hans-Peter Knopfel
  • Patent number: 6148603
    Abstract: In a method of operating a gas turbine group with low calorific value fuel, the gas turbine group essentially comprises a compressor, a combustion chamber, a turbine and a generator. The low calorific value fuel is compressed by means of a fuel compressor. Low calorific value fuel (11a) in excess of the stoichiometric quantity is mixed into part of the combustion air (9, 9a) during the starting of the gas turbine group so that a stable flame appears. After the attainment of the rated rotational speed (B) and synchronization, at the latest, the quantity of low calorific value fuel (11a) is reduced to such an extent that a ratio is attained which is just over the stoichiometric ratio. The rest of the low calorific value fuel (11b) is mixed into the rest of the combustion airflow (9a, 9b) in order to attain the desired load.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: November 21, 2000
    Assignee: Asea Brown Boveri AG
    Inventor: Rolf Althaus
  • Patent number: 6145315
    Abstract: In a process for preheating and deaerating make-up water in a power generation plant by steam, the required make-up water is initially heated up to the saturation temperature without substantial deaeration and is subsequently deaerated. The steam used for heating and deaerating is expanded steam from a condenser, which steam is almost fully condensed during the heating of the make-up water and is recycled to the steam circulation of the power generation plant.
    Type: Grant
    Filed: June 21, 1999
    Date of Patent: November 14, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Francisco Blangetti, Hans Eberle
  • Patent number: 6146478
    Abstract: A heat treatment process for material bodies made of a high-temperature-resistant iron-nickel superalloy of the type IN 706 comprises the following steps: solution annealing at approximately 965 to 995.degree. C. for 5 to 20 hours, stabilization annealing at approximately 775 to 835.degree. C. for 5 to 100 hours, and precipitation hardening at 715 to 745.degree. C. for 10 to 50 hours and at 595 to 625.degree. C. for 10 to 50 hours. A heat-treated material body of this kind, made of a high-temperature-resistant iron-nickel superalloy of the type IN 706 exhibits a crack growth rate of less than 0.05 mm/h and/or exhibits a minimum elongation of 2.5% without cracks at a constant strain rate of 0.05%/h and a temperature of 600.degree. C.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: November 14, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Werner Balbach, Gunnar Harkeg.ang.rd, Reiner Redecker
  • Patent number: 6141952
    Abstract: In a method of operating a combined-cycle plant, valves (21) acting upstream of a high-pressure steam turbine (12) are completely closed in the event of load shedding. The gas-turbine group (A+8) is uncoupled from an intermediate-pressure/low-pressure steam turbine (11) in such a way that the gas-turbine group can go into island mode. In this case, the speed of the uncoupled steam turbine (11) is not greater than the speed of the gas-turbine group (A+8), and steam (16) in the flow path of a reheater (10a) belonging to the heat-recovery steam generator (10) expands freely through the intermediate-pressure/low-pressure steam turbine (11), in the course of which this expansion does not cause the speed of the gas-turbine group (A+8) to exceed its protective speed.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: November 7, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Rolf Bachmann, Fredy Hausermann, Peter Muller, Gerhard Weiss
  • Patent number: 6140699
    Abstract: In a semiconductor clamped stack, in particular for high-power converters, a plurality of power semiconductor components are arranged alternately together with water-cooled cooling cans in a stack. A clear arrangement of all the components and supplies is achieved, and defective semiconductor components can be replaced more easily, in that a molding (10) according to the invention is used for holding in each case one heat sink and one power semiconductor component. Rails and latching-in fasteners are provided for guiding and holding the latter.
    Type: Grant
    Filed: July 1, 1999
    Date of Patent: October 31, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Urs Hildbrand, Thomas Keller, Christoph Stemmler