Impact of On-Load Tap Changer Operation on Voltage Control in Distribution Networks with High PV Penetration |
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P. Benavente, E. Sainz, L. Vejo, S. Bustamante, A. Laso, R. Martinez, A. Arroyo, M. Mañana Department of Electrical and Energy Engineering, Universidad de Cantabria, Spain
2026-06-27 |
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Abstract
High photovoltaic (PV) penetration in distribution networks creates increasing voltage regulation challenges due to the variability of generation and demand. Overvoltages during periods of high PV production and undervoltages during peak demand can compromise voltage quality compliance. Traditional voltage regulation based on fixed or off-load tap changers lacks flexibility and often requires planned outages.
This paper analyses the impact of on-load tap changer (OLTC) operation on voltage control in a distribution network. Time-series simulations are carried out on a representative feeder using synthetic load and PV profiles. Scenarios with and without OLTC are compared, and different OLTC control strategies are evaluated. Key performance indicators include voltage limit compliance and the effectiveness of tap operations.
Results show that OLTC operation significantly improves voltage regulation and mitigates voltage violations without supply interruptions. OLTCs are therefore confirmed as an effective solution for PV-rich distribution networks.
Key words: On-load tap changer, voltage regulation, photovoltaic integration, active distribution networks.
Published in: Energies
& Quality Journal (E&QJ) |
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| ISSUE: Vol. 4. No.1 | Pages: 43-47 |
| E-ISSN: 2659-8779 | Date of Current Version: 2026-06-27 |
| REF: 224-26 | Issue Date: 2026-07-15 |
| DOI:10.24084/eqj26-224 | Publisher: AEDERMACP/ EA4EPQ |
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