Naslov
Impact of power transformer energization on relay protection operation

Autori
Filipović-Grčić, Božidar ; Perković, Marijan ; Stipetić, Nina Stipetić

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Izvornik
EMTP User Conference 2021 / - , 2021

Skup
EMTP User Conference 2021

Mjesto i datum
Online; konferencija, 31.08.2021. - 07.09.2021

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
power transformer energization ; inrush currents ; relay protection ; saturation ; EMTP

Sažetak
One of the main causes of the incorrect operation of transformer relay protection are inrush currents. The transient inrush current occurs when energizing the unloaded transformer, and it is a consequence of the transformer core saturation. This paper presents analysis of transients caused by energization of 300 MVA three-phase autotransformer with stabilizing winding and voltage ratios 400/115/10, 47 kV. Using the PAMSUITE Toolbox in EMTP, many simulations were performed to show the impact of model’s parameters on the amplitude and duration of inrush currents as well as the probability of 2nd harmonic differential current amplitude occurrence. Simulation results show that controlled switching reduces inrush currents amplitudes and increases 2nd harmonic content in differential currents. A Protection Toolbox in EMTP was used for modelling CT saturation and operation of transformer’s differential protection relay. Based on the simulation results the optimal differential protection settings were determined, and the probability of false relay protection operation was calculated.

Izvorni jezik
Engleski

Znanstvena područja
Elektrotehnika

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