EARTH LEAKAGE CIRCUIT BREAKER BASED ON THE RATIO OF A SPECIFIC HARMONIC CURRENT COMPONENT TO THE FUNDAMENTAL WAVE CURRENT COMPONENT

    公开(公告)号:EP3496222A1

    公开(公告)日:2019-06-12

    申请号:EP18209668.5

    申请日:2018-11-30

    申请人: LSIS Co., Ltd.

    摘要: An earth leakage circuit breaker includes a current sensing unit configured to sense current in a circuit, a converter configured to detect a fundamental wave component and a specific harmonic component from the sensed current, the specific harmonic component being one of a plurality of harmonic components, and a controller.
    The controller is configured to compare a harmonic component ratio with a threshold component ratio, to determine whether the sensed current is abnormal current, and to control cutoff of the circuit according to the result of determination. The harmonic component ratio is a ratio of the specific harmonic component to the fundamental wave component. The converter is configured to convert the sensed current from an analog signal into digital data and to perform Fourier transform with respect to the converted digital data to detect the fundamental wave component and the specific harmonic component.