Discrimination between internal faults and inrush currents in power transformers using the wavelet transform

dc.contributor.author	Gaddala, Jaya Raju	en
dc.date.accessioned	2015-02-14T12:27:54Z
dc.date.available	2015-02-14T12:27:54Z
dc.date.issued	2015-02-14
dc.identifier.uri	http://hdl.handle.net/11400/6236
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://e-jst.teiath.gr/	en
dc.subject	Power systems
dc.subject	MATLAB software
dc.subject	Conventional protection scheme
dc.subject	Linear transformation
dc.subject	Συστήματα ισχύος
dc.subject	Λογισμικό MATLAB
dc.subject	Συμβατικό σύστημα προστασίας
dc.subject	Γραμμικός μετασχηματισμός
dc.title	Discrimination between internal faults and inrush currents in power transformers using the wavelet transform	en
heal.type	journalArticle
heal.classification	Technology
heal.classification	Engineering
heal.classification	Τεχνολογία
heal.classification	Μηχανική
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh85133147
heal.classificationURI	http://zbw.eu/stw/descriptor/19795-3
heal.classificationURI	N/A-Τεχνολογία
heal.classificationURI	N/A-Μηχανική
heal.language	en
heal.access	free
heal.publicationDate	2014
heal.bibliographicCitation	Gaddala, J.R. (2014). Discrimination between internal faults and inrush currents in power transformers using the wavelet transform. "e-Journal of Science & Technology". [Online] 9(1): 67-81. Available from: http://e-jst.teiath.gr/	en
heal.abstract	The power transformer protection plays vital role in power systems. Any power transformer protective scheme has to take into account the effect of magnetising inrush currents. Since during the energization of the transformer, sometimes results in 10 times full load currents and can cause mal operation of the relays. The ratio of the second harmonic to the fundamental harmonic of the inrush current is greater than that of the fault current. To avoid this we go for conventional protection scheme by sensing the large second harmonic. The second harmonic in these situations might be greater than the second harmonic in inrush currents. The differential power method has the disadvantage that the need to use voltage transforms and increased protection algorithm calculation cost. Neural networks have the disadvantage that it requires a large of learning patterns produced by simulation of various cases. This paper describes the discrimination between internal faults and inrush currents in power transformers using the wavelet transform based feature extraction technique. It is shown that the features extracted by the wavelet transform have a more distinctive property than those extracted by the fast Fourier transform due to the good time and frequency localization characteristics of the wavelet transform. The performance of this is demonstrated by simulation of different faults and switching conditions on a power transformer using MATLAB software.	en
heal.publisher	Νερατζής, Ηλίας	el
heal.publisher	Σιανούδης, Ιωάννης	el
heal.journalName	e-Journal of Science & Technology	en
heal.journalName	e-Περιοδικό Επιστήμης & Τεχνολογίας	el
heal.journalType	peer-reviewed
heal.fullTextAvailability	true