Protection selectivity analysis of a medium-voltage network with battery energy storage systems

Krličević, Faris (author), Bosović, Adnan (author)

V prispevku obravnavamo vpliv vključevanja baterijskih hranilnikov energije (BESS) na prispevke k kratkostičnim tokovom in selektivnost zaščite v 11-kV srednjenapetostnem omrežju v kraju Söderala na Švedskem. Analiza kratkostičnih razmer pri šibkem in močnem napajalnem omrežju pokaže, da je glavni vir okvarnih tokov na zbiralkah nadrejeno omrežje, medtem ko imajo lokalni baterijski hranilniki prevladujoč vpliv na okvare v njihovi neposredni električni bližini. Selektivnost zaščite smo ovrednotili z analizo časovno-tokovnih karakteristik in simulacijami kratkostičnih dogodkov v programu DIgSILENT PowerFactory. Rezultati potrjujejo ustrezno delovanje zaščitne sheme, ki omogoča odklop okvarjenega dela omrežja brez nepotrebnega izklapljanja nepoškodovanih odcepov. Ugotovitve kažejo, da lahko ustrezno usklajena klasična nadtokovna zaščita zagotavlja zanesljivo delovanje tudi v srednjenapetostnih omrežjih z velikim deležem pretvorniško priključenih virov.

• Language: Slovenian
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FE - Faculty of Electrical Engineering
• Publication date: 01.01.2026
• Year: 2026
• Number of pages: Str. 223-229
• Numbering: Letn. 93, št. 4
• PID: 20.500.12556/RUL-190011
• UDC: 621.316.9:621.311.243
• ISSN on article: 0013-5852
• COBISS.SI-ID: 301662723
• Publication date in RUL: 20.10.2026

Record is a part of a journal

• Title: Elektrotehniški vestnik
• Publisher: Strokovna zadruga koncesijoniranih elektrotehnikov, Elektrotehniška zveza Slovenije
• ISSN: 0013-5852
• COBISS.SI-ID: 742916

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: English
• Title: Analiza selektivnosti zaščite srednjenapetostnega omrežja z baterijskimi hranilniki energije

Abstract

The paper investigates the impact of Battery Energy Storage System (BESS) integration on short-circuit (SC) contribution and protection selectivity in an 11 kV medium-voltage (MV) network located in Söderala, Sweden. The SC analysis is performed under weak-grid and strong-grid operating conditions to evaluate the impact of the upstream grid strength on fault contribution at the main busbar and BESS feeder locations. The results show that the upstream grid remains the dominant fault source at the main busbar, while locally connected BESS units become the dominant contributors to faults located electrically closer to the converter-interfaced sources. The Protection selectivity is evaluated using Time–Current Characteristic (TCC) analysis and verified through ShortCircuit Trace (SC Trace) simulations in DIgSILENT PowerFactory. The implemented protection scheme demonstrates a satisfactory selectivity, where faults are isolated by the protection device associated with the faulted section without unnecessary disconnection of healthy feeders. The findings indicate that a properly coordinated conventional overcurrent protection can maintain a reliable operation in inverter-dominated MV systems.

• Keywords: battery energy storage system, protection selectivity, short-circuit analysis, overcurrent protection, medium-voltage network