| 摘要 |
<p>Disclosed isa micro-controller based accurate sensing of earth fault in presence of harmonics and thereby tripping under actual fault condition and thus reducing the number of nuisance trips. A method (200) for earth fault detection based on a signal received, thereby tripping said electronic tripping unit of said circuit breaker is disclosed. The method (200) comprises of extracting (202) fundamental components values from the signal received; calculating (204) earth current signal based on fundamental components extracted and initiating a timer (206), if sum of said earth current signal calculated exceeds a predefined threshold value, thereby tripping (208) said electronic tripping unit of said circuit breaker.</p> |
