Measuring transformer with a capacitor bushing
AssigneeSiemens Aktiengesellschaft
InventorsHans-Joachim Freygang, Gabor Kovacs
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Abstract
A measuring transformer arrangement with a capacitor bushing and devices for measuring voltage and current associated with the capacitor bushing is suitable for use in a high-voltage installation with metal encapsulation carrying several high-voltage conductors. The capacitor bushing provided for each high-voltage conductor is arranged in a bulkhead partition of the metal encapsulation and carries a current measuring device which includes at the periphery of the bushing at least one current transformer core with a secondary winding system mounted thereon.
Claims6
In a high-voltage, fluid-insulated switching installation having a metal enclosure and containing a plurality of high-voltage conductors, the metal enclosure including at least one metal bulkhead for dividing the metal enclosure into separate compartments and extending transverse to the conductors, a measuring transformer arrangement comprising:
- a plurality of feedthrough bushings mounted in the bulkhead and corresponding to respective ones of the high-voltage conductors for accommodating the same at the bulkhead;
- a plurality of voltage detection devices for detecting the voltage on corresponding ones of the high-voltage conductors, each of said voltage detection devices including capacitor means disposed in the bushing associated with the corresponding high-voltage conductor;
- and a plurality of current detection devices for detecting the current in corresponding ones of the high-voltage conductors, each of the current detection devices including a transformer unit arranged on the outer surface of the bushing associated with the corresponding high-voltage conductor, each of said current transformer units including a current transformer core, and a secondary winding system mounted on said core.
A measuring transformer arrangement suitable for installation in a fluid-insulated, high-voltage equipment such as in a high-voltage switching installation or the like having a metal enclosure and containing a plurality of high-voltage conductors, the metal enclosure including at least one bulkhead extending transverse to the high-voltage conductors, the measuring transformer arrangement comprising:
- a plurality of cast resin feedthrough bushings corresponding to respective ones of the high-voltage conductors for accommodating the same at the bulkhead;
- a plurality of voltage detection devices for detecting the voltage on corresponding ones of the high-voltage conductors, each of said voltage detection devices including capacitor means disposed in the bushing associated with the corresponding high-voltage conductor;
- a plurality of current detection devices for detecting the current in corresponding ones of the high-voltage conductors, each of the current detection devices including a transformer unit arranged on the outer surface of the bushing associated with the corresponding high-voltage conductor, each of said current transformer units including a current transformer core, and a secondary winding system mounted on said core;
- said capacitor means for each of said voltage detection devices comprising a control electrode arranged in the corresponding feedthrough bushing so as to be in surrounding relation to the high-voltage conductor accommodated therein, said control electrode and the high-voltage conductor conjointly defining a high-voltage capacitor;
- and, said voltage detection device further including a low-voltage capacitor connected to said control electrode;
- said high-voltage capacitor and said low-voltage capacitor conjointly defining a voltage divider, said control electrode being embedded in said cast resin feedthrough bushing;
- and grounded guard ring-electrodes embedded in said bushing and disposed on respective ends of said control electrode, said voltage detection device including an amplifier connected across said low-voltage capacitor.
Dependencies are inferred from the claim text.