Fault level calculations for protection of power system components

Τίτλος

Fault level calculations for protection of power system components

Θέμα

Electric fault location

Electric power systems--Protection

Δημιουργός

Kyriakides, Elias

Πηγή

Higher Technical Institute

Το πλήρες κείμενο είναι διαθέσιμο από το Υπουργείο Ενέργειας, Εμπορίου Βιομηχανίας και Τουρισμού.

Εκδότης

Library of Cyprus University of Technology

Ημερομηνία

1996

Συνεισφέρων

Chrysafiades, Ch.

Ioannou, Y.

Δικαιώματα

Απαγορεύεται η δημοσίευση ή αναπαραγωγή, ηλεκτρονική ή άλλη χωρίς τη γραπτή συγκατάθεση του δημιουργού και κάτοχου των πνευματικών δικαιωμάτων.

Μορφή

pdf

Γλώσσα

en

Τύπος

text

Αναγνωριστικό

EED0676

Σύνοψη

This project deals with calculating the expected fault levels at the busbars of the system under study, this being part of the Generation, Transmission and Distribution system of the Electricity Authority of Cyprus. These expected fault levels are required for the accurate
adjustment of the protective relays which will work during the transient period following the
fault. These relays are very important since they are responsible for clearing faults and protecting the system. As M. Kaufmann once said, the protective relays and the protective equipment in general, is the ambulance at the foot of the cliff rather than the fence at the top.
This implies that their function is not preventive since they take action only once a fault has occurred. Therefore special consideration should be given in adjusting the protective equipment according to the expected fault levels.
The project will concentrate on the modelling of power system components for the purpose of fault calculations. A Power System Analysis (PSA) package was used to calculate the expected fault levels.
The main conclusions drawn by this study, are that having more than one busbar at the Distribution side of a substation and deparalleling the feeders outgoing from these busbars, results in reduced fault levels due to increase of the impedance seen by the fault. Finally, as
will be shown, no need exists in changing the circuit breakers of the District Office substation for the period under consideration.