Porazdelitev električnega toka v talilnem elementu pri udarnem valu

KNEZ, AMADEJ (author), Vončina, Danijel (mentor)

V pričujočem diplomskem delu je raziskan vpliv debeline talilnega elementa na razporeditev gostote električnega toka znotraj prevodnika. Kožni pojav je analiziran v talilnem vložku, ki se uporablja v sklopu prenapetostne zaščite (angl. Surge Rated Fuses, SRF). V fazi razvoja SRF talilnega vložka so se pojavili dvomi o pravilnem dimenzioniranju talilnega elementa zaradi hitrih sprememb toka, ki se pojavijo ob prenapetosti, kot je udar strele, kar lahko povzroči kožni pojav znotraj talilnega elementa. V okviru diplomskega dela sem poskušal vpliv kožnega pojava zmanjšati s tanjšim talilnim elementom. Modeliranje talilnega elementa je izvedeno v programskem okolju Ansys Maxwell. Uporabljena je analiza z metodo končnih elementov, s katero je ocenjena razporeditev gostote električnega toka v obstoječem in v stanjšanem talilnem elementu. Prav tako so praktično preizkušeni vzorci talilnih vložkov z obstoječim in s stanjšanim talilnim elementom. Rezultati pokažejo, da s tanjšanjem talilnega elementa ne odpravimo kožnega pojava, ki otežuje doseganje želene izklopne karakteristike talilnega vložka. V prihodnje bi bilo treba preizkusiti še druge oblike in debeline talilnih elementov, ki bi lahko zmanjšali vpliv kožnega pojava.

• Language: Slovenian
• Keywords: talilni vložek, kožni pojav, tokovni udarni val, SRF, Ansys Maxwell.
• Work type: Bachelor thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2016
• PID: 20.500.12556/RUL-85549
• Publication date in RUL: 16.09.2016

Secondary language

• Language: English
• Title: Current distribution in fuse-element during surge test

Abstract

The main goal of the diploma thesis is to study the influence of the fuse-element thickness on the distribution of current density within the conductor. Skin effect is analyzed in the SRF fuse link, which is used as a part of overvoltage protection. During the development of the SRF fuse link doubts have arisen about the proper dimensioning of the fuse-element due to rapid current changes, which occur in overvoltages like lightning strikes. This can lead to skin effect within the fuse-element. The aim of the diploma thesis is to reduce the effects of this phenomenon by using thinner fuse-element. Fuse-element modeling is performed in the Ansys Maxwell program environment. Finite element analysis is used for evolution of current density distribution in the existing and thinner fuse-element. Additionally, samples of fuse links are tested practically with existing and thinner fuse-element. Results demonstrate that thinning the fuse-element does not eliminate the skin effect, making achievement of desired time current characteristic of fuse-link difficult. In the future, it would be necessary to study other shapes and thickness of the fuse-element, which could reduce the skin effect.

• Keywords: fuse link, skin effect, surge lightning pulse, SRF, Ansys Maxwell.