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

Abstract

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.

Dependencies are inferred from the claim text.