Asea Brown Boveri Ag

Andrzej Kaczkowski

Antonio Bosco

Marcel Fuglister

Manfred Seidel

Alfred Walter Jaussi

Markus Meng

Thomas Hertig

Current transformer for a metal-enclosed gas-insulated high-voltage installation

The capacitive voltage transformer is provided for a metal-enclosed, gas-filled high-voltage system. It has a cylindrical capacitor having two coaxially arranged, electrically conducting cylinders (12, 13), of which one internally arranged cylinder (12) is at a high voltage potential and outwardly bounds a current-carrying conductor (5) of the system. An externally arranged one of the two cylinders (13) is inserted in an electrically insulated fashion into the metal enclosure (4). In a first embodiment of the voltage transformer the internal cylinder (12) has an enclosing tube (16) formed from a material having a lower coefficient of linear thermal expansion than copper. In a second embodiment there is provided, for the purpose of correcting the transformed voltage values, a device which detects the value of the current carried in the conductor (5), and in which the change in the capacitance of the cylindrical capacitor is determined as a function of a change in temperature caused by the current carried in the conductor (5). The accuracy of the transformed voltage values is increased by both embodiments.

Capacitive voltage transformer for a metal-enclosed, gas-filled

The measuring device is intended for a metal-enclosed, gas-insulated high-voltage installation. It contains at least one sensor (10, 11), arranged in an enclosure tube (3) of the metal enclosure which is filled with insulating gas, and at least one electronic evaluation device (23, 23'), which processes output signals of the sensor (10, 11). The evaluation device (23, 23') and a plug-and-socket device (28, 28') connecting the evaluation device to an output of the sensor (10, 11) are arranged in a two-part metal housing. One part of this housing is formed by a hollow metal flange (26), integrally formed on the outer surface of the enclosure tube (3), and the region of the enclosure tube (3) rimmed by the hollow flange (26). The other part of the housing is a housing element (27) which is depressed in the shape of a trough and is fastened to the hollow metal flange (26) of the enclosure tube (3) by its edge, which delimits the trough opening. This measuring device is distinguished by a compact design and, because of the local control, by a high measuring accuracy and a high operational reliability.

Measuring device for a metal-enclosed, gas-insulated high-voltage

The measuring device is intended for a metal-enclosed, gas-insulated high-voltage installation. It contains at least one Rogovski coil (10), which is arranged in an enclosure tube (3), filled with insulating gas, of the metal enclosure and serves to detect the current in a current-carrying conductor (9), led through the enclosed tube (3), and a measuring electrode (11), which surrounds the conductor (9) and serves to detect the voltage of the conductor (9). The current conductor (9) is rigidly connected to a current-conducting cast armature (13) of an insulator (14) fastened to the enclosure tube (3). In the measuring device according to the invention, a defined field geometry is maintained in the interior of the enclosure tube (3) even over long periods and under changing loads. Consequently, the sensors, in particular the voltage sensor containing the measuring electrode (11), can transmit output signals of high measuring accuracy.

The Rogovski coil (1) is provided with a winding (2) applied to a winding support made from an insulating material. It has a central axis (4) and an opening (5), which is enclosed by the winding support and is penetrated by the central axis (4). A particularly homogeneous winding (2) and, associated therewith, very accurate current measurement are achieved by virtue of the fact that a surface, facing the central axis (4), of the winding support is provided with first stops (7), which are distributed on the circumference, extend in the direction of the central axis (4), and divide the winding (2) into winding segments (9). In this case, the spacing between in each case two of the first stops (7) is always an integral multiple of the diameter (D) of the wire forming the winding (2).

Growing community of inventors

Wurenlingen, Switzerland

Andrzej Kaczkowski