On determination of current and voltage vectors in the distribution network according to AIMS EMA

The paper deals with the problem of determining current and voltage vectors in a three-phase distribution electric network (DEN) with 0.4 kV voltage. It is believed that the resistances of the inter-subscriber DEN sections are unknown due to the fact that they can substantially depend on external factors (temperature, humidity, etc.). An automated information-measuring system of electricity monitoring and accounting (AIMS EMA) is functioning in the distribution network. Effective values of current and voltage, active and reactive power at the beginning of the monitored section of the DEN and at each of its subscribers are measured with AIMS EMA means simultaneously for the same observation interval. The authors analyzed the previously proposed “method of identifying currents and voltages inaccessible for measuring and monitoring”, which is based on the determination of current and voltage vectors by synthesizing an identifier of load dynamics using relative values and constants for their formation. Its shortcomings are shown and a new method for solving this problem is presented. The results obtained can be useful in the development of special software of subsystems for monitoring the electrical state, implemented as part of AIMS EMA.