Aksijalne vibracije namota energetskog transformatora

master's thesis

• Title (english): Axial vibrations of power transformer windings
• Author: Nikola Škreb
• Mentor: Marko Jokić (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2019-03-29, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Tema ovog diplomskog rada je izrada pojednostavljenog diskretiziranog numeričkog modela prikladnog za proračun aksijalnih vibracija namota transformatora.
U uvodnom dijelu rada je opisana teorija koja je potrebna za razumijevanje problematike. Opis izvedbe transformatora daje uvid u terminologiju i građu transformatora, dok teorija vibracija daje uvid u fiziku problema. Ukratko su opisani i konačni elementi primjenjeni u numeričkim analizama.
Poglavlje koje slijedi iza uvoda daje detaljan opis svih komponenti konkretnog energetskog transformatora tvrtke Končar Energetski Transformatori. Detaljan opis uključuje dimenzije dijelova, svojstva materijala od kojih su ti dijelovi izrađeni kao i način na koji su sve komponente međusobno pozicionirane u sklopu transformatora. Pritom su navedene i opisane nužne preinake svojstava materijala i dimenzija komponenti kako bi se omogućilo pojednostavljenje složenijih dijelova transformatora ili izbjegle moguće numeričke poteškoće.
Zatim su opisana dva numerička modela, jedan detaljniji u programskom paketu ANSYS, a drugi jednostavniji u programu MATLAB. Detaljniji model je predviđen za analizu metodom konačnih elemenata te su za njega navedene i opisane sve postavke definirane u programskom paketu ANSYS. Za matematički jednostavniji numerički model opisan je način sastavljanja potrebnih matrica te njihov sadržaj.
Nakon opisa numeričkih modela slijedi prikaz i usporedba rezultata. Rezultati su prvo uspoređivani za pojedine komponente te za jedan podsklop kako bi se jednostavni numerički model verificirao. Analize su pokazale da jednostavni model daje dobra rješenje za proračun vlastitih frekvencija. U posljednjem su poglavlju prikazani rezultati analize cijelog sklopa transformatora.

Abstract (english)

The subject of this master thesis is to create a simplified discretised numerical model, appropriate for the calculation of axial vibrations in transformer windings.
The content of the thesis introduction is theory required for understanding the issues that are being tackled. Transformer description gives an insight in the transformer construction and in the terminology that is being used. Theory of vibration gives an insight in the physics of the problem. A short description of the finite elements that were used is also given.
A detailed description of the transformer components is given in the chapter that follows the introduction. The mentioned power transformer was designed by the company Končar Energetski Transformatori. The detailed description includes part dimensions, material properties and part positions. Necessary modifications of material properties and part dimensions are listed and described. The modifications were introduced in order to simplify the complex transformer structures or to avoid possible numerical difficulties.
This is followed by numerical model descriptions. The detailed numerical model was prepared for the analysis in ANSYS, a finite element method based software. All the necessary steps in ANSYS are listed and described. The mathematically simpler numerical model was prepared for the analysis in MATLAB, a programming language that allows matrix manipulations. Matrix generation logic and matrix content is described.
Numerical model descriptions are then followed by the results and the results comparison. In order to verify the simpler numerical model, results are first compared for the individual parts and for one assembly. The analysis have shown that the simple model yields good solutions for the eigenfrequencies calculations. The results off the entire transformer analysis are presented in the last chapter of the paper.

• Keywords: Aksijalne vibracije namota transformatora; energetski transformator; metoda konačnih elemenata; proračun vlastitih frekvencija
• Keywords (english): Axial vibrations in transformer windings; power transformer; finite element method; eigenfrequencies calculations
• Language: croatian
• URN:NBN: urn:nbn:hr:235:900568
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2024-3-29
• Created on: 2019-05-23 00:38:29