Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Transient Stability During Asymmetrical Faults
KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
2015 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

This research project has been conducted at RTE in order to study the transient stability after

asymmetrical faults. When three-phase short-circuits occur in a network, almost all the electrical

power is lost on the relevant line(s). Among all short-circuit types, it is the most drastic event and the

issue has to be solved very quickly. But oddly, it is also the easiest problem to solve mathematically

speaking. This comes from the fact that the system stays balanced, and equations can be simplified.

However with line-to-ground faults this is no longer the case, and transient stability analysis becomes

tricky.

Until now, unbalanced situations have not been studied much. Since this kind of trouble is less

serious than losing all three phases, every protection devices on the network have been sized to

counter three-phase faults in time and avoid severe consequences. They will then also work for onephase

problems.

Despite this, there is a desire from RTE to understand

– physically and mathematically – what

happens when one-phase faults occur, and it is the mission behind this master thesis. First, a

mathematical theoretical model was derived to examine a

network’s stability without running any

simulation. Then, once simulation software programs were taken in hand, several tests were run on a

very simplified network, and compared with the theory developed previously. Finally, these

experiments were carried out on a much larger scale.

It is important to understand that, except for the theoretical model, all the results and conclusions in

this document come from simulations. Even if a lot of tests and models led to them, these

conclusions must be handled with care. The goal of this work was also to have a better

understanding of unbalanced systems, of the Fortescue representation and thus, understand more

clearly the parameters required by simulation tools like Eurostag© for future studies.

Abstract [sv]

Detta

forskningsprojekt

genomfördes

hos

RTE

för

att

undersöka

transientstabilitet

efterosymmetriska

fel.

När

trefasiga

kortslutningar

inträffar

i

en

nätverk

försvinner

nästan

all

kraft

i

derelevanta

ledningarna.

Bland

alla

kortslutningstyper

är

detta

den

mest

drastiska

händelsen

och

måstelösas

väldigt

snabbt.

Konstigt

nog

är

det

det

lättaste

problemet

att

lösa

matematiskt.

Detta

grundav

faktumet

att

systemet

förblir

balanserat

och

ekvationer

kan

förenklas.

Hursomhelst

vid

enfasigajordfel

är

detta

inte

längre

fallet

och

transientstabilitetsanalys

blir

plötsligt

svårt

att

räkna

på.

Fram

tills

nu

har

inte

lösningar

obalanserade

situationer

studerats

mycket.

Eftersom

denna

typ

avproblem

är

mindre

allvarliga

än

att

förlora

alla

tre

faser,

har

enheter

nätverket

utformats

för

attmotverka

trefas--‐fel

snabbt

och

undvika

allvarliga

konsekvenser.

Enheterna

kommer

också

fungeraför

enfasproblem.

Trots

detta

finns

det

en

önskan

från

RTE

att

förstå

–fysiskt

och

matematiskt

–vad

som

händer

närett

enfasproblem

uppstår,

det

är

det

som

är

målet

med

mitt

examensarbete.

Först

framtogs

enmatematisk

teoretisk

modell

för

att

examinera

nätverkets

stabilitet

utan

att

köra

någon

simulation.

Sedan

med

hjälp

av

mjukvarusimulatorer

utfördes

flertalet

test

med

den

tidigare

utveckladeteorin.

I

slutändan

utfördes

experimenten

i

en

mycket

större

skala.

Det

är

viktigt

att

förstå

att,

utom

den

teoretiska

modellen,

kommer

alla

resultat

i

denna

rapportenfrån

simuleringar.

Även

om

flera

tester

och

modeller

ledde

fram

till

dem,

ska

dessa

slutsatserhanteras

varsamt.

Målet

med

detta

arbete

var

att

bättre

förståelse

för

obalanserade

system,

representationen

med

symmetriska

komponenter

och

därmed,

en

klarare

förståelse

för

parametrarna

som

krävs

avsimuleringssverktyg

som

Eurostag©

för

framtida

studier.

Place, publisher, year, edition, pages
2015. , 75 p.
Series
EES Examensarbete / Master Thesis, XR-EE-ETK 2015:001
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:kth:diva-160521OAI: oai:DiVA.org:kth-160521DiVA: diva2:790038
External cooperation
RTE France
Educational program
Master of Science in Engineering - Electrical Engineering
Examiners
Available from: 2015-02-23 Created: 2015-02-23 Last updated: 2015-02-23Bibliographically approved

Open Access in DiVA

fulltext(2672 kB)310 downloads
File information
File name FULLTEXT01.pdfFile size 2672 kBChecksum SHA-512
6492c79bf0b4056d525c5c7d21f4f15772d1aa5e552b08809998db4563a70c4e5226467973f352f26550074a62750bd690dbf341678f6d8e83027f091a7ea441
Type fulltextMimetype application/pdf

By organisation
Electromagnetic Engineering
Other Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 310 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 262 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf