Lokalizace zemního spojení v radiální síti pomocí signálu HDO

Earth Fault Location in a Radial Network Using Remonte Control Signal

dissertation

Czech

Tato práce navazuje na experiment zabývající se možností identifikace místa zemního spojení v zkruhované síti pomocí signálu HDO provádený v druhé polovine roku 2001. Reší lokalizaci poruchy využitím nové metody, která by určila pravdepodobnou vzdálenost zemního spojení v radiální síti bez možnosti kruhování a pouze s využitím hodnot merených v rozvodne. Jedná se o pokus aplikace této metody v reálné distribucní síti, na základe jehož výsledku je zhodnocena možnost jejího praktického využití.

A single phase-to-ground connection is a fault that appears very frequently in MV lines of distribution networks. This fault can result in injuries of persons that occur near to the point of the fault and it can result as well in an interruption in the supply of electricity. Most distribution networks are operated as a compensated network, where an immediate disconnection of the fault is not necessary. The line can be operated without interruption, but only under condition that the fault is quickly located and eliminated. It means that a prompt fault identification and appropriate location guarantee at least uninterrupted energy supply. At present, digital protections using the admittance principle are able to identify quite reliably a single phase-to-ground connection and to determine the affected feeder. Still, the location of the fault presents a task yet to be solved. The main problem of a fault location consists is a low value of the fault current during a single phase-to-ground fault in compensated networks. This work is a continuation of an experiment performed in the second half of 2001. The experiment explored a possibility of the identification of a fault location in a circular network by means of remote load control signal. The work deals with a novel method for a fault location that is able to determine the distance of a fault in a radial network (without a possibility of a circular interconnection) using only values measured in a switching station. It presents the application of the method in a real distribution network and the evaluation of the results of this experiment.

Zemní spojení, lokalizace poruch v kompenzovaných sítích, nesymetrické zkraty, kompenzace zemních kapacitních proudů, zhášecí tlumivka, ochrany při zemních spojeních, distribuční sítě vn.

Phase-to-ground fault, distribution networks, fault location in compensated networks, unsymmetrical faults, Petersen coil, phase-to-ground protection.

ORSÁGOVÁ, J.

1. 1. 2004

Brno

1

68

68