Mitigating Voltage Unbalance in Modern Distribution Network with Distributed Energy Resources and Solar PV Inverters

Abstract

Maintaining voltage balance in distribution networks is increasingly challenging due to the rise of 1-phase DERs, [15] such as rooftop PV systems, and large 1-phase loads like electric vehicles, which can degrade power quality and reduce equipment efficiency. This study proposes a reactive power compensation strategy using PV inverters, employing two control frameworks: a decentralized controller using only local measurements, and a distributed controller coordinating multiple inverters via communication. Simulations on the IEEE 13-bus feeder under different load and PV conditions show that both controllers effectively improve voltage balance, with the distributed controller achieving superior performance, while the decentralized approach provides a simpler and more economical solution. These results demonstrate that inverter-based reactive power support is a practical and cost-effective method for enhancing voltage stability in high DER penetration networks.