Improved islanded operation of a diesel generator — PV microgrid with advanced inverter

Abstract

Microgrids are characterized as weak systems with poor power quality due to significant variations in frequency and/or voltage that can occur during sudden changes in load demand. This problem is exacerbated in cases where one of the power sources is tied to the microgrid through a grid-interactive inverter which is designed to trip when deviations in frequency and voltage exceed well-defined thresholds that are specified by interconnection standards. Numerous solutions with variable complexity are proposed in the literature, including the integration of battery storage systems. This paper presents a simple alternative method that does not require any hardware nor software for solving the inverter tripping problem. Field experiments show that using an advanced inverter with controllable voltage and frequency ride-through capability eliminates the inverter disconnection under any condition, thus improving system performance and reliability.