Paralelni rad transformatora u industrijskom postrojenju

professional thesis

• Title (english): Parallel operation of power transformers in industrial facility
• Author: Nikola Grgurić
• Mentor: Ivica Pavić (mentor)
• Committee member: Viktor Milardić (predsjednik povjerenstva)
• Committee member: Ivica Pavić (član povjerenstva)
• Committee member: Srđan Žutobradić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; Zagreb
• Defense date and country: 2019, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering

Abstract

Zadatak ovog rada je analizirati paralelni rad dva transformatora različitih snaga i napona kratkog spoja na konkretnom primjeru u elektroenergetskom sustavu Petrokemije, d.d.. Analiza je provedena s ciljem utvrđivanja utjecaja takvog rada na tokove snaga kao i definiranja optimalnih radnih stanja, odnosno prijenosnih omjera transformatora u slučaju obostrane ili pojedinačne regulacije pri različitim mrežnim naponima na koji su transformatori spojeni, a pri kojima su cirkulirajuće struje, preuzeta jalova snaga iz mreže i gubici najmanji. U teoretskom dijelu rada opisani su uvjeti za mogući paralelni rad transformatora, a detaljnije su opisani efekti takvog rada za transformatore različitih karakteristika, tj. pojava cirkulirajućih struja i utjecaj na tokove snaga. Opisano je modeliranje mreže nadomjesnim modelima elemenata mreže kao preduvjet za postavljanje jednadžbi za rješavanje tokova snage. Kao najbolje rješenje za proračun tokova snaga predstavljena je Newton-Raphsonova metoda za rješavanje nelinearnih jednadžbi. Praktični dio rada se temelji na simulaciji elektroenergetskog sustava u inženjersko programskom alatu ETAP® koji nudi mogućnosti analize, simulacije, praćenja, upravljanja, optimiziranja i automatizacije elektro energetskih sustava. Dobivene vrijednosti tokova snaga, napona i gubitaka u sustavu za razne pogonske slučajeve i prijenosne omjere transformatora dane su u tablicama, a njihovi međusobni odnosi prikazani su grafovima, pri čemu su definirana optimalna radna stanja transformatora u paralelnom radu.

Abstract (english)

The task of this paper is to analyze the parallel operation of two transformers with different power ratings and short circuit voltages on a specific example in the Petrokemija Plc electrical power system. The analysis was carried out with the aim of determining the impact of such operation on power flows as well as the definition of optimal operating conditions, i.e. the transformer ratios in case of mutual or individual regulation at different transformers main voltages, in which the circulating currents, the reactive power from the network and the losses are minimized. In the theoretical part of the work, the conditions for parallel operation of transformers and the effects of such operation for transformers with different parameters, i.e. the occurrence of circulating currents and the impact on power flows are described. The network modelling is described as a requirement for setting equations to solve load flow problem. The Newton-Raphson method is presented as the best technique for solving the set of various nonlinear equations of load flows. The practical part of the work is based on the simulation of the power system in the engineering software ETAP®, which offers the possibility of analyzing, simulation, monitoring, managing, optimizing and automation of electrical power systems. The obtained values of power flows, voltages and power losses in the system for various operating cases and the transformer ratios are given in the tables, and their interrelations are presented with graphs, where optimum operating conditions of the parallel transformers are defined.

• Keywords: transformatori
• Keywords (english): transformers
• Language: croatian
• URN:NBN: urn:nbn:hr:168:943006
• Study programme: Title: Postgraduate specialist Study in Transformers; Study programme type: university; Study level: postgraduate specialist; Academic / professional title: sveučilišni/a specijalist/specijalistica transformatora (sveučilišni/a specijalist/specijalistica transformatora)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2022-07-07 12:31:09