FIELD: electric power industry and electrical engineering.
SUBSTANCE: phase voltages and currents of emergency and pre-emergency modes are measured at the beginning of a controlled transmission line. For direct, reverse and zero sequences, corresponding bidirectional models of homogeneous sections of the controlled line are created based on two identical internal models, the first of which converts the input voltage and current from left to right, and the second - from right to left. By cascading the models of homogeneous sections, bidirectional models of a controlled power transmission line are built for each sequence, in which pre-emergency and purely emergency voltages and currents are determined at the output of the first internal model and normalized electrical quantities at the output of the second internal model of each homogeneity section. For a homogeneous area with a presumed damage site, for each sequence, a model of the damaged area is created based on the two mentioned internal models, the first of which converts the input values from the left side to the estimated damage site, and the second - from the right. In the model of the damaged section of each sequence, purely emergency voltage and current are determined to the left of the alleged fault location and normalized voltage and current to the right of the alleged fault location of the corresponding sequences. The purely emergency current on the right side of the supposed fault location of each sequence is determined in proportion to the normalized current to the right of the alleged fault location of the sequence of the same name, and the proportionality coefficient is determined by dividing the purely emergency voltage to the left of the alleged fault location by the normalized voltage to the right of the alleged fault location of the corresponding sequences. The closing current of each sequence is determined as the sum of purely emergency currents of the same sequences to the left and to the right of the alleged fault location. The emergency mode voltage at the expected fault location for each sequence is determined. The reactive parameter of the alleged damage site is formed and the point at which the reactive parameter takes a zero value is taken as the damage site.
EFFECT: simplification of the method through the use of bidirectional models of a controlled transmission line.
7 cl, 4 dwg
Authors
Dates
2023-02-28—Published
2022-06-14—Filed