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. Phase currents and voltages unsynchronized in time are measured from both ends of the line during a short circuit, damaged phases are determined. The oscillograms from the two ends of the line are combined along the cut of the beginning of the short circuit. At a given interval from the beginning of the short circuit, the cross section is selected on the oscillograms of the current and voltage of the damaged phase, and the instantaneous values of the currents i' , i'' and stresses u', u'' in the section are recorded. In this case, the accuracy of determining the location of a short circuit is preliminarily set with an error not exceeding the length of one span of an overhead power transmission line. An iterative procedure is carried out according to the golden section method. During the iterative procedure, the values of voltage drops to the short circuit point relative to the beginning and end of the overhead power line are estimated based on the instantaneous values of currents i', i'' and stresses u', u'' of the damaged phase in the cross section of the oscillograms, taking into account the change in resistance in non-uniform sections of the overhead power line. Completion of the iterative procedure is carried out when the accuracy of calculating the distance to the place of the short circuit is not worse than the specified accuracy. As the objective function of the iterative procedure to be minimized, the modulus of the voltage drop difference to the short circuit point relative to the beginning and end of the overhead power line is selected.

EFFECT: improving the accuracy of determining the location of a short circuit under conditions of a non-uniform distribution of resistivity along the line.

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