Method and device for testing protection relays
AssigneeMegger Sweden AB
InventorsAndrea Bonetti, Stefan Larsson, Peter Werelius, Lennart Schottenius, Gustav Östberg
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Abstract
An analog accessory for use in a system for testing protection relays is provided, comprising inputs connectable to the current outputs of a test-set for protection relays and voltage outputs connectable to a protection relay to be tested. By providing an electric circuit adapted to convert current provided by the test-set into a voltage signal on the voltage outputs that simulates an output of a Rogowski sensor, A system and a method for testing protection relays are also provided.
Claims17
An analog accessory for use in a system for testing protection relays, comprising:
- inputs connectable to current outputs of a test-set for protection relays
- voltage outputs connectable to a protection relay to be tested, and
- an electric circuit adapted to convert current provided by the test-set into a voltage signal on the voltage outputs that simulates an output of a Rogowski sensor
- wherein the electric circuit comprises a transformer having a core, a primary winding electrically connected to the inputs and a secondary winding electrically connected to the voltage outputs.
A method of testing protection relays, the method comprising the following steps:
- providing, by means of a relay test-set, a user settable primary current representing a fault condition,
- providing, by means of an analog accessory, a voltage signal representing the derivative of the primary current by simulating the behaviour of a Rogowski coil, and
- supplying the voltage signal to a protection relay to be tested, wherein the relay test-set is set in a mode for a Rogowski coil;
- wherein the electric circuit comprises a transformer having a core, a primary winding electrically connected to the inputs and a secondary winding electrically connected to the voltage outputs.
Dependencies are inferred from the claim text.