Abstract:
A method and a system for determining a circular characteristic for distance protection of a three-phase electric line, the system comprising means for detecting a fault on the electric line, means for identifying a faulted phase or phases of the electric line, means for determining, at a measuring point, a first fault loop impedance by using voltage(s) of the faulted phase(s), a second fault loop impedance by using a polarization voltage and a third fault loop impedance by using predetermined line parameters, and means for determining a radius and midpoint of the circular characteristic.
Abstract:
The invention relates to a fuse system for a switchgear assembly, especially for a medium voltage switchgear assembly. The fuse system comprises a plurality of fuses which correspond to the number of phases, every fuse having a tripping bar that projects from the face of the fuse under the effect of the force of a spring when the fuse comes into action. A sealing body, with a spring arrangement interposed, pushes a sealing head into the interior of a receptacle receiving the fuse. A two-armed lever is received on the sealing head, one arm covering a tripping mechanism which actuates a power switch.
Abstract:
A reverse-conducting semiconductor device includes a freewheeling diode and an insulated gate bipolar transistor (IGBT) on a common wafer. Part of the wafer forms a base layer with a base layer thickness. The IGBT includes a collector side and an emitter side arranged on opposite sides of the wafer. A first layer of a first conductivity type and a second layer of a second conductivity type are alternately arranged on the collector side. The first layer includes at least one first region with a first region width and at least one first pilot region with a first pilot region width. The second layer includes at least one second region with a second region width and at least one second pilot region with a second pilot region width. Each second region width is equal to or larger than the base layer thickness, whereas each first region width is smaller than the base layer thickness. Each second pilot region width is larger than each first pilot region width. Each first pilot region width is equal to or larger than two times the base layer thickness, and the sum of the areas of the second pilot regions is larger than the sum of the areas of the first pilot regions.
Abstract:
A method and an apparatus for showing data representative of the accuracy of switching operations executed by a high-voltage switchgear which is operatively coupled to a power line and to a synchronous switching device. Data related to switching operations executed by the high-voltage switchgear is recorded and then, based on the recorded data, values indicative of the accuracy of the switching operations executed with respect to predefined target switching operations are calculated. A histogram is formed using the calculated values and shown to a user.
Abstract:
A digital relay, for regulating the operation of a power distribution apparatus, comprising a computerized interface, which includes at least a computerized module providing HTTP (Hyper Text Transfer Protocol) services.
Abstract:
A device for breaking DC currents exceeding 2500 A has a resonance circuit connected in parallel with an interrupter and a surge arrester connected in parallel with the resonance circuit. The resonance circuit has a series connection of a capacitor and an inductance. The relationship of the capacitance in μF to the inductance in μH of the resonance circuit is ≧1.
Abstract:
The exemplary embodiments relate to an autonomous temperature transmitter for use in process installations. In order to feed an electronic component with energy, a thermoelectric transducer is arranged such that it is thermally operatively connected to at least one thermal conducting element between an internal thermal coupling element and an external thermal coupling element, the internal thermal coupling element being thermally coupled to the process medium and the ambient air flowing around the external thermal coupling element.
Abstract:
A Medium Voltage circuit breaker which comprises a pole assembly having, for each phase, an interruption chamber housing a first fixed contact and a second movable contact reciprocally couplable/uncouplable between an open and close position; the Medium Voltage circuit breaker further comprises an actuator to actuate the opening and closing operation of said circuit breaker and an insulating base frame supporting said pole assembly and said actuator.
Abstract:
A switching device for an electrical switchgear assembly for power distribution includes a grounding function unit including a first moving control element selectably moveable to a first manual operation position and an isolation function unit including a second moving control element selectably to a second manual operation position. The grounding function unit is selectable to a manual operation state by moving the first moving control element to the first manual operation position, and the isolation function unit function unit is selectable to a manual operation state by moving the second moving control element to the second manual operation position. When the manual operation state is selected for one of the grounding and isolation function units, selection of the other of the grounding and isolation functional units to the manual operation state is blocked by a respective one of the first and second moving control elements.
Abstract:
Exemplary embodiments are directed to a test arrangement for testing surge voltage in electrical high voltage components with a surge voltage generator and a voltage distributor. The surge voltage generator and voltage distributor have a tower-like structure with a first and a second structure end. A rectangular container is connected to the first and second structure and includes a first and a second container end. At least one of the surge voltage generator and the voltage distributor are movable between a first substantially horizontal position inside the container and a substantially vertical position relative to the container. Each movement between the two positions involves a pivot motion about a rotational axis perpendicular to the longitudinal direction of the surge voltage generator.