Метод расчёта и мониторинга параметров распределительной сети, контролируемой автоматизированной информационно-измерительной системой учёта электроэнергии

Abstract

The paper considers a four-wire distribution electric network (DEN) with a voltage of 0.4 kV, in which electrical parameters, namely the complex resistances of inter-subscriber sections of the DEN, are calculated by means of an automated information and measuring system of electricity metering. The parameters are determined on the basis of voltages and currents effective values simultaneous measurements, as well as the phase displacement angles between them at the beginning of the network and at all of its subscribers. The measurements are performed by the accounting system for the same observation interval. In this case, the complex resistances of all phase (linear) wires are taken to be the same within the interpersonal sections of the network and it is taken into account that they may differ from the resistance of the neutral wire. To solve this problem, a for assessing of three-phase network variables inaccessible for measurement and control was proposed previously. In the present work, the disadvantages of this method are revealed and a new method for calculating and monitoring the parameters of the DEN is proposed. In this case, the data of two different modes of the DEN operation are used, which are obtained on the basis of the changes analysis in the supply voltages and currents. The analysis is performed by the head unit of the metering system. The results obtained are focused on the implementation of new functions in metering systems: monitoring of the technical condition of the DEN and power losses in it in real time.