Metodologija proračuna raspodjele unutarnjih prenapona duž namota transformatora primjenom koncentriranih parametara

doctoral thesis

• Title (english): Methodology for calculation of transformer windings'internal overvoltage distribution using lumped parameters
• Author: Tomislav Župan
• Mentor: Željko Štih (mentor)
• Committee member: Željko Štih (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electrical Engineering Fundamentals and Measurements); Zagreb
• Defense date and country: 2016, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering; Electromechanical Engineering
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

Zbog svoje važnosti za elektroenergetski sustav, transformatori se projektiraju kako bi, uz stacionarne, bili u mogućnosti izdržati i situacije mogućih prijelaznih stanja u električnoj mreži. Zbog toga postoji potreba za kvalitetnim visokofrekvencijskim modelom namota transformatora. Ova disertacija se bavi izradom nadomjesnog visokofrekvencijskog modela namota transformatora pomoću metode koncentriranih parametara. Prikazana metodologija se zasniva na internom modelu te nastoji predvidjeti raspodjelu napona duž namota uslijed brzorastućih prijelaznih pojava. Svi parametri modela su određeni korištenjem numeričkih metoda zasnovanih na metodi momenata. Nadomjesni model namota je analiziran u vremenskoj i u frekvencijskoj domeni. Prikazana je metodologija određivanja raspodjele napona duž namota te proračun rezonantnih frekvencija namota transformatora. Model je verificiran mjerenjima na posebno konstruiranom modelu transformatora. Utvrđena je zadovoljavajuća točnost prikazanog nadomjesnog modela te mogućnost određivanja rezonantnih frekvencija namota i naponskih naprezanja duž namota.

Abstract (english)

Transformers are vital to every electric power system. Due to various switching operations and atmospheric discharges, they are exposed to numerous overvoltages and have to be designed to correctly operate in those circumstances. Therefore, adequate mathematical models are needed to study their behavior at voltages with high frequency components. This dissertation presents the methodology for obtaining the high frequency model of transformer windings. The model is of internal type and is based on lumped parameters. All the parameter values are obtained using numerical methods based on the method of moments. Obtained transformer model is analyzed both in time and in frequency domain. The winding’s internal overvoltage distribution and the winding’s resonant frequency analysis is presented. Experimental verification of the developed numerical model has been done on a specially constructed transformer. Measurements are in a good agreement with calculated results.

• Keywords: prijelazne pojave; visokofrekvencijski model transformatora; koncentrirani parametri; metoda momenata; vremenska domena; frekvencijska domena; rezonantna analiza
• Keywords (english): transient overvoltages; high frequency transformer model; lumped parameters; numerical calculations; method of moments; time domain; frequency domain; resonant analysis
• Language: croatian
• URN:NBN: urn:nbn:hr:168:951322
• Study programme: Title: Electrical Engineering and Computing; Study programme type: university; Study level: postgraduate; Academic / professional title: Doktor znanosti elektrotehnike i računarstva (Doktor znanosti elektrotehnike i računarstva)
• Type of resource: Text
• Extent: 144 str. ; 30 cm.
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2019-04-11 14:20:57