METHOD FOR DETERMINING LOCATION OF A SHORT CIRCUIT ON AN OVERHEAD POWER LINE WITH UNSYNCHRONIZED MEASUREMENTS FROM ITS TWO ENDS Russian patent published in 2023 - IPC G01R31/08 

FIELD: electric power industry.

SUBSTANCE: invention can be used to determine the location of a short circuit on power lines during unsynchronized measurements from its two ends. Essence: measured from both ends of the line (' - one end of the line,'' - the second end of the line) instantaneous values of phase currents (i'_A, i'_B, i'_C), (i''_A, i''_B, i''_C) and stresses (u'_A, u'_B, u'_C), (u''_A, u''_B, u''_C) during a short circuit, receive their oscillograms. The oscillograms from the two ends of the line are combined along the cut of the beginning of the short circuit. Arrays are formed from successive instantaneous values for each of the oscillograms of the current and voltage of the damaged phase i' (m), i'' (m), u' (m), u'' (m), determine the first time derivatives of the currents for the selected arrays of instantaneous values di'(m)/ dt_m, di''(m)/ dt_m, as well as the first and second derivatives of the voltages du'(m)/ dt_m, du''(m)/ dt_m, d²u'(m)/ dt²_m, d²u''(m)/ dt²_m. The voltage matrices U 1 and U 2 are formed using the active resistance R, inductance L and transverse capacitance C of the power line, instantaneous values of arrays of currents, voltages i'(m), i''(m), u'(m), u''(m), as well as the instantaneous values of the derivatives of currents and voltages. The relative value of the distance to the short circuit n is determined using the voltage matrices U 1 and U 2 and the least squares method. Based on the obtained relative value of the distance to the place of the short circuit n, the distance to the place of the short circuit is determined from the side of the end with the index '.

EFFECT: improving the accuracy of determining the location of a short circuit under conditions of deviations of currents and voltages from a sinusoidal shape, taking into account the distributed capacitance of power transmission lines.

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