This thesis presents the problem of transient single-phase-to-earth faults elimination in medium voltage networks. These faults have a large share of the total number of errors and their removal would significantly improve power quality regarding uninterruptible consumer supply. Elimination is done with the system that uses three single pole shunt circuit breakers. It grounds the medium voltage sub phase in which fault occurred in a defined time interval and thus puts out the fault current on the original fault location. If the failure was transient, normal operating conditions will establish and the consumers will not experience interruption of power supply. The thesis presents introductory underlying problems. Theoretical considerations of single-phase-to-earth faults in medium voltage networks and different methods of neutral point grounding are shown. After analyzing the basic parameters of different types of neutral point grounding, a reference to the practice and impact on the power supply is given. The transient single-phase-to-earth faults elimination system and requirements for the system components are defined. The installation of the suggested system in a 35/20 kV substation, which was a pilot project in Croatia, is described, along with the representation of the operations on the primary and secondary facilities. The system operation is presented then, including analysis of previously collected statistical data, the electrical conditions in a cycle of work and overvoltage problems during shunt switching. The impacts of the system on substation protective earthing are presented. The evaluation of the system is given by defining the network suitable for the installation of the system, stating the advantages and disadvantages of the system and the economic aspect of implementation. Improving possibilities of the proposed system are elaborated, including system connection modus, interaction with the relay system and removal of defined deficiencies Final thoughts on the presented subject are given at the end of the thesis.