Frequency of occurrence of voltages of specific size to occur at the nodes of distribution and transmission power systems in case of a three-phase short circuit, as identified by definition

The paper considers the problems of group and cumulative group distribution of the frequency of occurrence of residual node voltages of a specific size that occur in specific parts of the power system in the Czech Republic in case of a three-phase short circuit at the nodes. The results are shown in the corresponding bar graphs, and evaluated and compared each with other at the end of the paper. Furthermore, the impact of impedance of the 400(220)/110 kV transformer on the voltage drop originating in the power system´s nodes during the short circuit are evaluated.