Assessment of Local Photovoltaic Inverter Control Strategies and transformer tap control for Voltage Regulation in Low-Voltage Distribution Networks
O. Abarrategi, E. Torres, D.M. Larruskain, V. Valverde, I. Zamora Department of Electrical Engineering, School of Engineering in Bilbao, University of the Basque Country EHU, Bilbao, Spain 2026-06-27

Abstract

The increasing penetration of photovoltaic (PV) systems and electric vehicles in low-voltage distribution networks (LVDNs) has intensified voltage regulation challenges due to bidirectional power flows and limited network flexibility. Conventional solutions based on infrastructure reinforcement or centralized control are often costly and complex to deploy. This paper analyzes a local voltage control strategy that exploits the inherent capabilities of PV inverters to provide voltage support in LVDNs with high PV penetration. The proposed approach relies solely on local measurements, eliminating communication requirements, and employs reactive power control and, when necessary, active power modulation to maintain voltages within regulatory limits. Simulation results under representative operating conditions demonstrate the effectiveness of the proposed local control in mitigating overvoltages while reducing active power curtailment. The combination with transformer tap control enables performance of voltage regulation.

Key words: Low-voltage distribution networks, Photovoltaic inverters, Voltage control, Reactive power control, Active power curtailment, Distributed Energy Resources.

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