Vol.3, No 1, 2006 pp. 15 - 26
UDC
368.025.61
PROTECTION OF DISTRIBUTIVE POWER TRANSFORMERS AND THE PROFESSIONAL RISK
Vladica Aleksić1, Zoran Stajić2, Milan Radić2
1Electric Power Distribution Company, Vranje
2Faculty of Electronic Engineering, Niš
Abstract.
This paper considers the correlation between the operation of distributive power transformers' protection systems and the level of professional risk in distributive substations. The main functional segments of a typical substation of 110/35/10 kV and its operation have been described. Also, the typical protection systems of three-winding distributive power transformer 110/36.75/10.5 kV, 31.5/31.5/10.5 MVA have been mentioned. Special attention has been paid to the reserve earth-fault protection system, which is identified as the cause of a serious problem in the parallel operation of two distributive power transformers. Besides the argumentation of the applied protection system inadequacy, some suggestions for revision of certain technical recommendations are given. The acceptance of these suggestions will make the operation of distributive substations more reliable and safe, decreasing the level of professional risk, at the same time.
Key Words:
Professional Risk, Power Transformer, Parallel Operation,
Protection System
ZAŠTITA DISTRIBUTIVNIH ENERGETSKIH TRANSFORMATORA I PROFESIONALNI RIZIK
U radu se razmatra odnos između načina rada sistema zaštite distributivnih energetskih transformatora i nivoa profesionalnog rizika u distributivnim trafo-stanicama. Opisani su glavni funkcionalni delovi i rad tipične trafo-stanice 110/35/10 kV. Navedeni su tipični sistemi zaštite koji se primenjuju kod tronamotajnih transformatora 100/36.75/10.5 kV snage 31.5/31.5/10.5 MVA. Posebna pažnja je posvećena radu sistema rezervne zemljospojne zaštite koji je identifikovan kao uzrok pojave ozbiljnih problema pri paralelnom radu dva energetska transformatora. Osim toga što je argumentovana neadekvatnost ovog sistema zaštite, date su sugestije za izmenu odgovarajućih tehničkih preporuka kojima se definiše način realizacije sistema rezervne zemljospojne zaštite. Uvažavanje ovih sugestija dovešće do pouzdanijeg i bezbednijeg rada energetskih transformatora u distributivnim trafo-stanicama 110/35/10 kV, što će istovremeno za posledicu imati smanjenje nivoa profesionalnog rizika.
Ključne reči:
profesionalni rizik, sistem zaštite, energetski transformator, paralelan rad
