Energy Storage System (ESS) for Compensating Unbalanced Multi-microgrids Using Modified Reverse Droop Control

TL;DR

This paper proposes a modified reverse droop control scheme for energy storage systems to improve voltage quality and reduce unbalance in multi-microgrid systems, validated through real-time simulation.

Contribution

Introduction of a modified reverse droop control scheme combining reactive power and voltage compensation for multi-microgrids.

Findings

Voltage unbalance factor reduced from 3.6% to 0.25%.

Reactive power consumption decreased significantly.

Enhanced voltage quality at the point of common coupling.

Abstract

The connection of single-phase microgrids (MG) and loads to three-phase MGs creates power quality problems such as unbalanced voltage and voltage rise at the point of common coupling (PCC) of the MGs. In this paper, a modified reverse droop control (MRDC) scheme in the Energy Storage System (ESS) is proposed to improve the three-phase PCC voltage quality in multi-microgrids (MMG). The MRDC consists of a reactive power compensator (RPC) and a voltage compensator. The controller regulates the reactive power and voltage unbalance of the MMG by using the reactive power produced by the ESS. The effectiveness of this proposed scheme is verified in real-time simulation using the Opal-RT OP5600 real-time simulator. The voltage unbalance factor (VUF) at the PCC is decreased from 3.6 percent to 0.25 percent, while the reactive power is reduced significantly at the single-phase load.