When the fault is being solved in 22 kV network, it is necessary to begin with detection which specific part of the line was or still is the main reason of the fault. A fast and reliable fault location enables to minimize the number of consumers affected by the fault and to reduce the time they are without electricity supply. This will leads to increased service reliability and to decreased operating cost of distribution network operator.

Nowadays used bisecting method is often time-consuming and it does not use all available information about power network at all. Therefore it is necessary to find a method, which will be based on the utilization of all available information from 22 kV network’s operation, as are the values of measured quantities (voltages, currents,…), the signalization of switching devices status, protection relays signalization and information obtained from calling customers. The method will respect not only the topology and the structure of the 22 kV network but also the way of its operation.

The algorithms of up to now developed methods utilize always only one of above mentioned methods for fault location. Their functionality was tested only by simulations, in which the real conditions of 22 kV network’s operation were not taken into consideration. We want to focus our project on these problems that have been overlooked up to now, e.g. the influence of real operation measurement (instantaneous values are not available), the existence of cable sections and overhead sections within one line and the fault location by multiple faults.

The investigation of possible application of expert system for fault location is another benefit of proposed project. The suitability of expert system to process and to evaluate information, which is obtained from distribution medium voltage network and is needed for fault location and fault type identification, will be investigated during the project.