Tugai Y. The models and methods for analyzing of high voltage electrical networks abnormal states.

The object of research: stationary and quasi-stationary electromagnetic processes in high voltage electrical networks. The purpose of research: development of the modeling theory and analysis of electrical networks modes, under the influence of external factors distortion of their parameters and changes in the internal structure for working out of system functionality conservation measures as a whole. Methods of research: tensor analysis methods of systems, analysis methods of multiphase electrical circuits, fuzzy logic methods, nonlinear dynamics methods and deterministic chaos theory, numerical integration methods and mathematical modeling. Theoretical and practical results and innovations: a new analyzing method of abnormal state in electrical networks with heterogeneous energy transport routes is developed; a new method of high-voltage distribution network reconfiguration is developed; the theoretical principles further development of normalization mode of trunk transmission line using controlled transmission lines of the new design with enhanced electromagnetic interaction phases are obtained; mathematical model for the study of quasi-stationary open-phase modes of transmission lines is improved; a new model of quasi-stationary modes in an electrical circuit with nonlinear inductance is developed; for the first time a method for dangerous oscillations damping in a nonlinear circuit with a voltage transformer by injecting into it an electromotive force is proposed; a method of ferroresonant process fixation is improved. A subject degree of introduction: developed compensation reactor is implemented at 750 kV substations and Ukrainian NPP; controlled transmission lines are in the experimental operation; serial production of ferroresonance damping device and the study’s results are used in the normative document of the Ministry of energy and coal industry of Ukraine and are introduced for mandatory use in all power systems of the National power company "Ukrenergo". Effectiveness of implantation: electric networks reliability with distortion circuit factors and state is improved; electric energy undersupply is reduced. Sphere of use: high voltage electrical networks.