Unapređenje konstrukcije energetskih transformatora u cilju smanjenja dodatnih gubitaka

doctoral thesis

• Title (english): Improvement of power transformer design in order to reduce stray losses
• Author: Žarko Janić
• Mentor: Željko Štih (mentor)
• Mentor: Zvonimir Valković (komentor)
• Committee member: Zlatko Maljković (član povjerenstva)
• Committee member: Željko Štih (član povjerenstva)
• Committee member: Zvonimir Valković (član povjerenstva)
• Committee member: Sead Berberović (član povjerenstva)
• Committee member: Ivo Uglešić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electrical Engineering Fundamentals and Measurements); Zagreb
• Defense date and country: 2008-06-06, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering; Electromechanical Engineering
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

U radu su analizirane metode smanjivanja dodatnih gubitaka transformatora izvan namota. Rad se fokusirao na lokalizaciju gubitaka. Za analizu je korišten program baziran na metodi konačnih elemenata, komercijalnog naziva MagNet. U prvom dijelu su istraživni gubici u kotlu i stezniku transformatora. Razmatrani su utjecaji različitih promjena u konstrukciji na gubitke. Istraživani utjecaji visine i širine magnetskih zaslona na kotlu, kao i udaljenost kotla od namota, na gubitke u kotlu. Napravljena je i ekonomska analiza optimalne izvedbe zaslona transformatora za tri razmatrana transformatora bitno različith nazivnih snaga. Analiza je rađena na osnovu kapitalizirane cijene transformatora. Razmatrani su i utjecaji veličine, položaja i materijala učvršćenja na stezniku, tzv. konzola, na gubitke u stezniku. Napravljeni su modeli kojima se na brz i jednostavan način može izračunati gubitke u zaslonjenom kotlu i u stezniku. Računi su bazirani na analitičkom računu i statistici. U drugom su dijelu razmatran je utjecaj spiralnog tipa namota na gubitke u kotlu i na gubitke uslijed površinskog učinka u višenaponskom namotu. Utjecaj konfiguracije velikoamperskim spojnica je također razmatran. Analizirane su prednosti i mane pojedinih konfiguracija. Na kraju su dane usporedbe nekoliko mjerenja sa računa iz MagNeta. Uspoređivana su mjerenja gubitaka na komercijalnim jedinicama te mjerenja magnetske indukcije na istraživačkom laboratorijskom modelu sa proračunima u MagNetu.

Abstract (english)

Stray loss reduction methods for losses outside the windings were analysed in this work. The work focused on the localisation of the loss. A program based on the finite element method was used in this work. The comercial name of the programme is MagNet. Tank and clamping losses were analysed in the first part of the work. Impact of construction changes on the loss were analysed. Impact of magnetic tank shields height and wideness, and distance between the shields (tank) and coils, on the tank loss were analysed. A cost-benefit analysis of the optimal tank shielding was made on three transformers of substantialy different nominal power. The analisys was made based on the capitalised cost of the transformer. An analisys of the bracket's size, position and material on the clamping loss was made. And finally matematical models for fast and easy calculation of loss in the shielded tank and clampings was made. The model is based on analical calculation and statistical data. Impact of the helical winding on the tank loss and eddy current loss in the high-voltage windings was analysed in the second part of the work. The Impact of the configuration of the high – current conductors was also analysed. Advantages and disadvantages of different configurations were explored. On the end of the work few comparisons of the measurements and calculations are given. Comparisons of loss measurements on commercial transformers and magnetic induction measurements on a research transformer with calculations from MagNet were done.

• Keywords: transformator; dodatni gubici; kotao; magnetski zasloni; steznik; spiralni namot; metoda konačnih elemenata
• Keywords (english): transformer; stray loss; eddy current loss; tank; magnetic shields; clampings; helical winding; finite element method
• Language: croatian
• URN:NBN: urn:nbn:hr:168:764566
• Study programme: Title: Doctoral study programme "Electrical Engineering and Computing"; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, po-dručje tehničkih znanosti (doktor/doktorica znanosti, po-dručje tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2020-05-21 12:20:56