Frequency Regulation in Isolated Microgrids Through Optimal Droop Gain and Voltage Control

Abstract

This article presents an adaptive active power droop controller and voltage setpoint control in isolated microgrids for optimal frequency response and stability after disturbances. The control scheme involves an optimal and model predictive control approach that continuously adjusts the active power droop gains and the voltage setpoints of Distributed Energy Resources (DERs) to maintain the frequency of the system within acceptable limits and enhance the primary frequency response of the system, while taking into account the active power sensitivity of the microgrid loads to the system’s operating voltage. The proposed control scheme is tested, validated, and compared with previously proposed techniques using time-domain simulations for a test system based on a CIGRE medium voltage benchmark microgrid under different realistic conditions, demonstrating the advantages of the proposed approach.