Моделювання періодичних електромагнітних процесів в силових трансформаторах електроенергетичних систем

Abstract

Dissertation research is devoted to the solution of complex problem of enhancing energy efficiency of electric supply systems by means of improvement of power transformers application in electric grids in order to reduce electric energy losses and ameliorate its quality, as well as further develop performance characteristics. The following scientific results are obtained in the research: It is shown, that application the theory of electromagnetic circuits in the process of mathematical models of electric engineering devices construction enables to reduce them to normal Cauchy form and this will allow to analyze both transient and steady-state periodic electromagnetic processes in power transformers on a common methodological base. Analytical presentation of power transformers models in normal Cauchy form makes them universal, that enables to develop the method of assessment of power transformer equipment impact on energy efficiency of electric energy supply and substantiate the construction of power transformers with space magnetic core, their application creates the conditions for energy losses reduction in the process of its transmission and improvement of voltage quality in electric grids. Development of new objects and study of the existing ones, are connected with the solution of problems, related to the sphere of analysis or synthesis. Efficiency of their solution depends on the methods of sensitivity assessment. The research further develops the method of assessment of mathematical model of the transformer sensitivity to output data as a result of determination of sensitivity matrix elements from the system of variation equations, analytical solutions of which are presented by the product of two multipliers: first of them is the matrix of transient reaction coefficients of state equation system and the second – exponential curve, that suppresses transient reaction, that enables to unite in a single algorithm all the stages of analysis of electromagnetic devices – calculation of transient and steady-state processes, determination of their static stability. Practical value of the research is that models, methods and recommendations, suggested in the research, can be applied in organizations, that carry out the research and analysis of electromagnetic processes while formation of electric energy systems development strategy, optimization of the plans of investments in the development of element base of energy systems. In particular, the developments of the given research enable to widen functional possibilities of design offices by means of using separate modules and standard subprograms. Main results of the research are introduced in practical activity of Public Joint-Stock Company “Khmelnitskoblenergo”, on the base of these results three-phase 100 kVA transformer of 10/0.4 kV with monolithic magnetic system and 25 kVA group transformer of 10/0.4 kV were manufactured. Theoretical principles, methods and models, determining scientific novelty of the dissertation, are used in educational process for training specialists of electric engineering specialties at Khmelnitski National University