Although much effort has been invested so far in the search and development of the original VF simulation transformer model, there is still no clear agreement which simulation model is adequate for the analysis of switching phenomena. The most important difficulties around which there is no unified approach are how to design a transformer core model with modeled all effects, nonlinear and frequency dependent behavior of many concentrated transformer parameters and inadequate determination of many input concentrating parameters. The mathematical models of the ideal HV switch and the high frequency distributive transformer of various forces and group of compounds were explored and presented in the dissertation. In addition, and not lees important, the remaining mathematical models of electrical power lines and loads required for the researched configuration of the simulation model are shown. The doctoral dissertation gives arguments on the most important issues related to the modeling of a high frequency energy transformer applied in the simulation of high frequency transient surges. In the appropriate and original way it presents the development of the VF transformer model and in Matlab - SimPowerSystems it analyzes the obtained simulation results for research switching cases. The assessment of the applicability of the developed frequency - dependent simulation transformer model is also presented and discussed in two examples. First, when the real coil is loaded with nominal power and secuund when the unloaded transformer switch off. Simulation testing has shown that the circuit breaker characteristic created by the circuit breaker operation is heavily dependent on the topology of the simulated network. Furthermore, it is shown how the amount of overvoltage switches is changed with considering to the switch - off moment. In addition, a model for analyzing the initial distribution of transient overvoltage in the HV transformer coil has been developed within the PhD dissertation. Moreover, the contribution to this paper is a graphical user interface that enables the generation of different form overvoltage characteristics with the purpose of analyzing the impact on the initial distribution of transient overvoltages on transformers of different rated power. Furthermore, different impacts of changing the configuration of the primary HV and secondary LV circuits to the value and shape of the switching overvoltage are simulated. XXIII Especially simulated effects of changing the ratio of total capacities to the primary HV winding inductance with the value of analyzing the influence on the shape characteristics of the initial distribution of the transient overvoltage. Especially for the selected switching cases, the effects of total, interphase and interwinding capacities on the switching overvoltage characteristic are analyzed. Among other things, the aim of the doctoral dissertation is to describe in detail the procedure for collecting and determining concentrated HF transformer parameters that are necessary for describing and using it. By using this approach, the basis for various simulated switching impacts is developed and expanded, and thus more precise analysis of the compiled configuration parameters of the configuration network. Parallel with this, a graphical user interface is developed to simulate different switch cases. The doctoral dissertation specifically describes measures and ways to reduce the negative effects of switching overvoltage. The aim of the dissertation is partly to improve the existing developed model of transformers in Matlab - SimPowerSystems, and partly to improve this model experimentally and analytically in laboratory conditions. For the purpose of realizing the remaining scientific contributions, a laboratory setup was designed. The simulator model of the laboratory transformer was designed with the aim of experimental verification on the example of a small inductance current. The laboratory setup consists of a laboratory transformer, a rapid LV switch, and a capacitive load. The obtained measurement results show the occurrence of a fast transient with a switching characteristic. For the purposes of the evaluation, the analytical models of the low inductance current circuit breaker and the real damper disconnection were used. It has been shown that the analytical models of the load shutdown and the low inductance current cuts with the expected accuracy reflect the experimental and simulation results.