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.

Development and application of vacuum circuit breaker model in electromagnetic transient simulation

Abstract: Vacuum circuit breakers (VCB) have excellent interruption and dielectric recovery characteristics, and can interrupt the high frequency currents, which result from arc instability. The interruption of these high frequency currents leads to multiple reignitions when the breakers are opening and severe voltage escalations under certain network conditions. The main aim of the paper is to model the vacuum circuit breaker in PSCAD that replicates the original breaker characteristics. The model developed simulates the occurrence of these transients. The model incorporates the random nature of arcing time, current chopping, dielectric strength and the quenching capability of the breaker. The developed breaker model for 3-/spl Phi/ VCB is implemented in a practical circuit employing switching off an arc furnace transformer and the results are presented.

Secondary burner having a through-flow helmholtz resonator

Abstract: In a secondary burner for a gas turbine combustion chamber, a fuel feed (2, 3) arranged in a combustion chamber wall (1) is surrounded by an annular air duct (4). The air duct (4) communicates, by means of at least one supply tube (5), with a through-flow Helmholtz resonator (6). The outlet from the Helmholtz resonator damping tube (7), which is configured as an annular duct, is located in the region of the burner mouth (8) in the secondary combustion space (9).

Defect detection system for identifying defects in weld seams

Abstract: The invention relates to a defect detection system for identifying defects in weld seams Said system comprises a scanner device, which is mounted on a displacement device of a processing unit and which can be displaced by said unit over at least one weld seam that is to be examined The scanner unit scans the weld seam using a predefinable frequency, each scanning sweep being correlated with a time signal and the time signal being used to record the point in time when at least one location containing defects is scanned The system is equipped with an analysis module to determine the co-ordinates of the defects from the signals that are obtained by means of the scanning sweeps The analysis module also stores the co-ordinates of the defects and transmits them to a localisation module The localisation module determines the spatial arrangement of the defects of the weld seam by evaluating the speed profile of the displacement device during the scanning sweeps, the time signal that is assigned to the scanned location containing defects and the co-ordinates of the defects that are provided by the analysis module

Remote diagnostic system for robots

Abstract: A remote diagnostic system for robots including a number of at least two robots, wherein a controller of each robot of the system is locally connected to a service unit provided with local processing power, a remote service center provided with a connector server is arranged, and a communications infrastructure for transferring packets of information between a controller of a robot of the system and connector server via the service unit is arranged for performing remote monitoring and diagnostics at the remote service center, wherein the communications infrastructure uses internet and/or GPRS communication lines.

Method for producing metal films

Abstract: A method for producing full-surface or partial metal films on a substrate includes placing a coating on a substrate. The coating is irradiated sheetwise with a laser to form the metal films.