Determining the location of damage in electrical networks 35-10-6 kV by an analytical method based on matrix equations of the 3rd degree with respect to voltages

Abstract

The article investigates an analytical method for determining the fault location in 35 kV, 10 kV and 6 kV networks based on thirddegree matrix equations for voltages. The method is remote, with doublesided measurement, according to the emergency mode parameters, the mode parameters are voltages and currents at the beginning and at the end of the line. The case is considered when the errors in determining the location of the damage are calculated theoretical and, as shown by the calculations, are only 1% both for metal closures and for pair closures through the contact resistance. Actual errors will depend on the accuracy classes of current transformers, voltage transformers, voltmeters and ammeters, for example: 0.2 - 0.5 - 2.0 - 5.0. The case is considered with an error of ±5%. The annual economic effect per 1 feeder with a really possible error of 5% is 170 thousand rubles when replacing only the method and 230 thousand rubles when replacing both the method and the device. For 1000 feeders, the annual economic effect will be 170 million rubles and 230 million rubles, respectively. Thus, the considered analytical method for determining the location of damage is effective both from a technical and economic point of view.