FIELD: energy.
SUBSTANCE: invention relates to power industry and can be used to determine the short circuit at long overhead power lines with spur line. Concept of the invention is as follows: a line model is pre-formed in three-phase form with taking into account mutual inductance and capacitance coupling between wires of lines capacitance coupling between wire and ground. In case of short circuit, values of complex phase voltages on buses and phase currents in line are measured and recorded before and at the moment of short circuit. Line model is divided into equal segments. Pre-fault voltages and currents are generated and stored at ends of each segment in each phase. Phase voltage modules are identified at ends of each segment in each phase. Values of complex pre-fault phase voltages and currents are identified from stored voltages and currents in the known point of spur line disposition. Phase currents of the spur line are defined as a difference of phase currents segments, adjacent to the spur line from one and another ends of the line, and spur line conductivities phase values are determined by division of phase complex currents of the spur line by phase complex voltages in the spur line assembly, spur line conductivities phase values include line and transformer conductivities from the spur line to load and spur line load conductivity. Values of phase voltages on buses and currents at both ends of the line measured at short circuit are determined by oscillograms of digital emergency processes recorder. Voltages are generated and stored at short circuit at the end of each area in each phase, starting from buses from one and another ends of the line. Currents are generated and stored at short circuit at the end of each area in each phase, starting from buses from one and another ends of the line. Modules of the phase voltages are identified at ends of each segment in each phase, starting from buses from one and another ends of the line. Diagrams of dependence of voltage modules from number of segment (or from distance) with axes on both sides are plotted along voltage modules at short circuit. Intersection point of these curves from one and another ends of line, different from the spur line point, corresponds to point of short circuit.
EFFECT: technical result is increased accuracy of determining the fault location.
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