Relejna zaštita centraliziranih sustava za kompenzaciju jalove snage u srednjenaponskim postrojenjima

scientific master's theses

• Title (english): Centralized capacitor banks relay protection in medium voltage substations
• Author: Zoran Grahovac
• Mentor: Ante Marušić (mentor)
• Committee member: Tomislav Tomiša (predsjednik povjerenstva)
• Committee member: Ante Marušić (član povjerenstva)
• Committee member: Srđan Žutobradić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Energy and Power Systems); Zagreb
• Defense date and country: 2011-12-02, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

U svojim početcima, ideja kompenzacije jalove snage razvijala se iz sasvim tehničkih razloga, dakle radi smanjenja nepovoljnih utjecaja tokova jalove snage kroz elektroenergetsku mrežu. Sa pojavom tržišta električne energije, sustavi za kompenzaciju jalove snage počeli su značajno dobivati na važnosti, jer su gubici vezani uz tokove jalove snage poprimili financijski karakter. Iz očitih razloga želja je korisnika osigurati maksimalnu raspoloživost opreme za kompenzaciju jalove snage, te ju zaštiti od mogućih kvarova koji mogu nastupiti u redovnom pogonu. To je osigurano upotrebom vrhunskih numeričkih uređaja relejne zaštite, specifično razvijenih za te potrebe. U radu je prikazana metodologija relejne zaštite koja je danas u širokoj upotrebi u statičkim srednjenaponskim postrojenjima za kompenzaciju jalove snage. Izvršena je analiza strujno–naponskih događaja u normalnim i kvarnim pogonskim stanjima kondenzatorskih baterija i sukladno tome detaljno su opisane funkcije relejne zaštite za njihovo štićenje. Osim toga, prikazan je utjecaj viših strujnih i naponskih harmonika na rad spomenute relejne zaštite, koordinacija relejnih i primarnih zaštita baterije, te zahtjevi na mjerne transformatore i utjecaj njihove točnosti na zaštitu. Završni dio obrađuje odabir i načine podešenja releja, sa posebnim naglaskom na balansne zaštite. Za kvalitetniju ilustraciju izveden je praktičan proračun i podešenje zaštite realnog primjera sustava za kompenzaciju jalove snage.

Abstract (english)

In earlier times, whole idea of reactive power compensation was developed to cancel and avoid most of the technical issues concerning reactive power flow through the power grid. Only recently it has been approached much more seriously, due to liberal electric power market, costs and penalties connected with reactive power consumption. Consequently, with development of numerical protective relaying, whole range of protection functions has been implemented to make shunt capacitor banks as reliable and useful as possible. This work concentrates on relay protection of medium voltage capacitor banks, used for power factor correction throughout medium voltage power grid. Specifically, it analyses transient switching states in normal conditions, as well as capacitor bank external and internal fault conditions, backed up with protection functions designed to sense and clear faults in minimum time, with minimum bank damage. Additionally, the effect of harmonic currents and voltages, primary and relay protection coordination, and instrument transformers requirements and accuracy have been described in detail. Finally, there is relay setting philosophy analysis, and application of settings for one real example of medium voltage shunt capacitor bank. Special focus is on unbalance protection functions.

• Keywords: srednjenaponske kondenzatorske baterije; kompenzacija jalove snage; relejna zaštita; podešenje zaštite
• Keywords (english): medium voltage shunt capacitor banks; reactive power compensation; relay protection theory of operation; application of settings
• Language: croatian
• URN:NBN: urn:nbn:hr:168:377841
• Study programme: Title: Postgraduate master programme in electrical engineering; Study programme type: university; Study level: postgraduate; Academic / professional title: Magistar znanosti elektrotehnike (Magistar znanosti elektrotehnike)
• Catalog URL: http://lib.fer.hr/cgi-bin/koha/opac-detail.pl?biblionumber=37235
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2020-08-27 09:34:24