Assessment of isolated power system frequency defense mechanisms

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F49777513%3A23220%2F17%3A43932391" target="_blank" >RIV/49777513:23220/17:43932391 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Assessment of isolated power system frequency defense mechanisms

Original language description

Under frequency load shedding (UFLS) is a mechanism that helps the TSO to preserve frequency as much close to 50 Hz during negative frequency changes greater than l Hz (resp. 1 - 1.9 Hz, 4 levels) by disconnection of 50% of the connected load in all. Unfortunately there are cases such as transition in to a stable island operation of a part of the electrical power system where the immediate disconnection of the connected load (via UFLS) during the primary regulation process might bring useless frequency collapse and blackstart needs. This situation is presented on an example system where the generated electrical power in the area of electrical island is average but slíghtly lower than currently consumed electrical power in the moment of transition in to island operation. This state causes a transient process with frequency drop under the limit of first level of UFLS for few seconds resulting in the acceptable frequency range of 49 - 50 Hz. Following paper describes generally situations that are threatened by the current settings of UFLS (given by the national grid code) based on real data from exemplary power system causing needless instability of the system and loss of operation primary thanks to sudden dangerous frequency jump over 50 Hz. In the next part of the paper other approaches to isolated system frequency defense mechanisms are ssessed (e.g. rate of change of frequency - RoCoF) in the view of safe transition in to the island operation. In the end examples of use in north parts of United Kingdom and Ireland are presented as possible approach to the question of frequency defense in states such as island operation of the part of the Czech power system. Influence of these mechanisms is modelled as well as the UFLS.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

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OECD FORD branch

20201 - Electrical and electronic engineering

Project

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Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Article name in the collection

Proceedings of the 9th International Scientific Symposium on Electrical Power Engineering (ELEKTROENERGETIKA 2017)

ISBN

978-80-553-3195-9

ISSN

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e-ISSN

neuvedeno

Number of pages

4

Pages from-to

623-626

Publisher name

Technical University of Košice

Place of publication

Košice

Event location

Stará Lesná, Slovenská republika

Event date

Sep 12, 2017

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

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