Participation of distributed resources and responsive loads to voltage unbalance compensation in islanded microgrids

Abstract

This study presents a new method for voltage unbalance compensation in islanded microgrids using distributed resources (i.e. distributed generations, storage systems) and responsive loads. The proposed method adopts the Newton trust-region approach to perform the load flow calculation. The sensitivity coefficients obtained from the load flow solution are incorporated into an optimisation problem whose cost function is defined based on voltage unbalance factor at all microgrid buses. The problem is solved using the particle swarm optimisation method. The results of the optimisation method in the form of correction commands are transmitted to the responsive loads and resources via a communication structure. The responsive resources even those with limited capacity and various types of loads including residential, commercial, and industrial are considered in the presented studies. In order to evaluate the performance of the proposed strategy, two different cases, namely, with and without energy storage devices, are simulated. Simulation results confirm the effectiveness of the proposed method in the voltage unbalance correction of islanded microgrids.