ANFIS-Based Add-On Controller for Unbalance Voltage Compensation in a Low-Voltage Microgrid

This paper presents an adaptive add-on controller for the unbalance voltage compensation in a low-voltage microgrid (LVMG) constituting multiple voltage source converters (VSCs) based distributed generation. The VSC-based LVMG is almost inertia-less system and any kind of load variations has a very significant impact on the voltage profile, which is highly undesirable. Presence of unbalance load at point of common coupling further exaggerates the problem. In order to mitigate the negative effect of unbalance load, an adaptive neuro-fuzzy inference system (ANFIS)-based add-on control loop has been added to the conventional VSC control. Here, the add-on controller sets the reference current gains equivalent to the voltage unbalance factor. These reference current gains obtained from the add-on controller are added to the output of a voltage control loop to set the modified reference current for an inner current control loop. The extensive simulation results with experimental validation have been provided to validate the proposed control algorithm.