ABB Ltd

About: ABB Ltd is a company organization based out in Zurich, Switzerland. It is known for research contribution in the topics: Voltage & Signal. The organization has 6222 authors who have published 6852 publications receiving 83994 citations.

Arrangement of holes for forming a cooling film

Abstract: Arrangement of holes for forming a cooling film on a wall (50) which is subjected to a flow of hot gas. Two rows (1, 2) of holes (10, 20) are provided which are arranged adjacent to one another, the diameter (d1) of the upstream holes (10) being smaller than the diameter (d2) of the upstream holes (20). The number of upstream holes (10) is equal to or smaller than the number of downstream holes (20). The use of such an arrangement of holes achieves the formation of an extremely effective cooling film with a simultaneously small consumption of cooling air.

Grate for a firing system

Abstract: The grate for a firing system has at least one rate conveyor having a plurality of fixed bar rows and moving bar rows alternating in the longitudinal direction, which are limited on both sides by side walls and which are composed of water-cooled grate plates (3; 4). These grate plates are provided with a multiplicity of orifices or slits (8) , arranged in groups, for the supply of primary air and are each pivotably connected respectively to a fixed and a movable grate plate carrier (6) in the region of their rear end and rest with their front end on the adjacent grate plate. In order to cool optimally the grate plates (3; 4) subjected to high thermal stress, there are provided, on the underside of the grate plate, at least in some grate plates, cooling ducts (9) which are located between the orifices or slits (8) , these cooling ducts being formed, on the one hand, by the grate plate itself and, on the other hand, by hollow profiles (10) attached to the grate plate.

Zoning in High Voltage DC (HVDC) Grids using Hybrid DC breaker

Abstract: Inter-regional dc grids can be defined as systems characterized by multiple protection zones. The build-up and operation of large dc grids will require isolating healthy sections or zones of the network from zones with faults. The rapid collapse of the dc voltage in case of faults requires components with very fast response times. ABB’s hybrid dc breaker technology boasts of response times of ~2 ms which will enable the operation and protection of large dc grids. From the hybrid breaker principles towards an 11 terminal system with control and protection details, the feasibility of the zoning concept is demonstrated.

Method and apparatus for producing three-phase current

Abstract: Exemplary embodiments are directed to methods and systems for producing a three-phase current to a three-phase output. Switching converters are used to generate a positive current, a negative current, and an intermediate current. The system is configured such that the produced positive current follows a path of a highest phase of a sinusoidal three-phase signal at a given time, the produced negative current follows a path of a lowest phase of the three-phase signal at the given time, and the produced intermediate current follows a path of a phase of the three-phase signal between the highest and the lowest phase at the given time. The produced currents are switched to each phase conductor of the three-phase output in sequence so that phase currents of the three-phase current are formed in the output conductors.

MOS-controlled thyristor (MCT)

Abstract: In an MOS-controlled thyristor MCT comprising a multiplicity of adjacently disposed individual MCT cells (MC) having a cell width and which are electrically connected in parallel, either the MCT cells (MC) themselves or cell clusters (15) comprising a few closest-packed MCT cells (MC) are mutually separated by nonemitting gaps (2) which do not inject charge carriers into the cathode base layer and which have lateral linear dimensions greater than or at least equal to the cell width of the MCT cells (MC). As a result of this separation, the full performance of the individual MCT cell (MC) is achieved even in large-area components containing many cells.