On modelling unbalanced distributive networks incorporated in ASCAE

The three-phase distributive electrical networks (DEN) 0.4 kV are considered under the conditions of electrical variables asymmetry and the introduction of the automated system of control and accounting of electricity (ASCAE). Thus the main objective of the automated system of control and accounting of electricity (ASCAE) is the commercial accounting of electricity. At the same time to improve the system effectiveness most relevantly it should include the following functional tasks: real-time monitoring and diagnostics of the DEN state, as well as optimization of the modes of its operation. The solution of these tasks is based on the mathematical models and methods, which ensure real-time identification of unmeasured and uncontrolled variables (current, voltage) of the three-phase network, which alows evaluating such quality indicators as the actual loss of electricity, as well as evaluate the current values of the parameters (resistance) of the trunk line using measurement data. The use of the known models and methods for this is connected with certain difficulties, caused by the asymmetry of the DEN mode, incomplete and uncertain input data used for the mathematical description of the network processes. Methodology to build up a model of asymmetrical three-phase network and to identify its electrical variables, unavailable for measurement, in real time is proposed. The results are meant to be used in the ASCAE for operational monitoring of the DEN electrical state and the evaluation of power losses in the network.