Digital Line Differential Protection Using Symmetrical Components
نویسنده
چکیده
A neuj method for digital line differential protection is presented. The protection compares the time function and the orthogonal function of the symmetrical positive-sequence component at the input and output o f a transmission line. From these values the magnitude of the differential current is evaluated. The time function is calculated according to the SD4c algorithm and the orthogonal function according to the SD4s algorithm from four sampled triplets. The first results of the investigation are shown. By using this method, a phase-independent operating time of less than half a period can be obtained.
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