Adaptive VAR Control for Distribution Circuits With Photovoltaic Generators

TLDR

The study presents an adaptive control algorithm that improves distributed reactive power control in radial distribution circuits with high PV penetration by balancing voltage regulation and power loss minimization. The algorithm adapts by selecting either power‑loss or voltage‑regulation objectives based on node voltage proximity to the substation, controlling PV inverter reactive power using local real and reactive power measurements. Simulations on a single‑branch radial circuit demonstrate that the adaptive scheme effectively reduces voltage variations while minimizing power loss, outperforming previously reported local and global control methods.

Abstract

We show how an adaptive control algorithm can improve the performance of distributed reactive power control in a radial distribution circuit with a high penetration of photovoltaic (PV) cells. The adaptive algorithm is designed to balance the need for power quality (voltage regulation) with the desire to minimize power loss. The adaptation law determines whether the objective function minimizes power losses or voltage regulation based on whether the voltage at each node remains close enough to the voltage at the substation. The reactive power is controlled through the inverter on the PV cells. The control signals are determined based on local instantaneous measurements of the real and reactive power at each node. We use the example of a single branch radial distribution circuit to demonstrate the ability of the adaptive scheme to effectively reduce voltage variations while simultaneously minimizing the power loss in the studied cases. Simulations verify that the adaptive schemes compares favorably with local and global schemes previously reported in the literature.