Method and system for detecting an arc fault in a power circuit using frequency response

摘要

A method of detecting an arc fault in a power circuit includes injecting an AC-signal into the power circuit and measuring a response signal that is related to the injected AC-signal in the power circuit. The method further includes determining a frequency response of the power circuit from the response signal, analyzing the frequency response, and identifying a preferred frequency. A signal related to AC-current flowing in the power circuit within the preferred frequency range is measured and an occurrence of an arc fault in the power circuit is signaled depending on the measured signal. A system for detecting an arc fault is designed to perform a method as described before.

主权项

1. A method of detecting an arc fault in a power circuit, the method comprising:
a) injecting an AC-signal into the power circuit; b) measuring a response signal related to the injected AC-signal within the power circuit; c) determining a frequency response of the power circuit from the response signal; d) analyzing the frequency response and identifying a preferred frequency range; wherein the preferred frequency range is chosen to be located around a minimum of the impedance curve; e) measuring a signal related to AC-current flowing in the power circuit within the preferred frequency range; and f) signaling an occurrence of an arc fault in the power circuit depending on the measured signal.