Shcherba M. Calculation of three-dimensional electric fields in nonlinear polymeric insulation of ultrahigh voltage cables

The object of research: three-dimensional electric fields in real dielectrics, in particular in polymeric insulation of electric power cables. The purpose of research: development of new scientific concept for calculation of three-dimensional electric fields in polymeric insulation of ultrahigh-voltage cables by developing numerical methods for solving Maxwell's equations in partial derivatives with simultaneous consideration of nonlinear properties of insulation, peculiarities of its microdefects and the presence of strong coupling between electro-physical processes. The research methods were based on the fundamental basis of the theory of electromagnetic field, mathematical physics, solid-state physics and thermodynamics. Theoretical and practical results and novelty: the theory of electromagnetic fields in real dielectrics has been developed by developing a scientific concept for calculating three-dimensional electric fields in polymeric insulation of ultrahigh-voltage cables based on the numerical solution of Maxwell's equations in partial derivatives and the use of finite element methods, Newton-Ruffson, LU- decomposition and algorithm for the analysis of interrelated processes, which allows to take into account simultaneously the nonlinear electrical characteristics of insulation, configuration of its micro-defects and strong coupling between the emerging electro-physical processes. Subject and degree of implementation: the main results of the dissertation were implemented at PJSC "Pivdencable Works" (Kharkiv), at the Institute of Electrodynamics of the National Academy of Sciences of Ukraine (Kyiv), at the Institute of Pulse Processes and Technologies of the National Academy of Sciences of Ukraine (Mykolaiv), in the National Technical University of Ukraine " Igor Sikorsky Kiev Polytechnic Institute", in the Admiral Makarov National University of Shipbuilding (Mykolaiv). Efficiency of implementation: significant technical and economical effect is obtained due to development of a new criterion for assessing the quality of modern polymer insulation of ultra high voltage cables as well as development of the method for determining the configurations and sizes of defects filled with copper melt in the four-layer thermal insulation lining of induction channel furnaces for the industrial production of high-quality copper rod. Scope of application: electrical appliances and devices.