Patent ID: 7864492

Claim:
An electrical fault detection device, comprising: a high-frequency sensor coupled to an electrical distribution line for detecting a high-frequency component of a sinusoidal electrical power signal, the high frequency sensor adapted to allow passage of high frequency signals and reject low frequency signals; a series arc-detection circuit coupled to the high-frequency sensor and including: a high-frequency module configured to identify and reject one or more narrowband portions of the high frequency component and identify a broadband portion of the high frequency component; a detection module configured to: rectify the sinusoidal electrical power signal; store a fault count value representing a propensity of the high-frequency component to be an arc fault; adjust the fault count value based on at least one characteristic of the broadband portion, the at least one characteristic including one or more of a quarter-cycle amplitude of the broadband portion during the quarter cycle following a zero crossing of the rectified sinusoidal electrical power signal, a non-quarter-cycle amplitude of the broadband portion after the quarter cycle, and a rate-of-change of the amplitude of the broadband portion, wherein each of the at least one characteristic has a respective weighted adjustment factor defining an amount by which the fault count value is adjusted upon detection of the at least one characteristic; and generate a series-arc trip signal if the fault count value exceeds a fault count threshold; and a trip circuit responsive to the series-arc trip signal for opening the electrical distribution line.