What are the key differences between grid-forming and grid-following inverters, and how do they influence microgrid operation?

Grid-forming and grid-following inverters are two fundamental types of inverters used to interface distributed energy resources (DERs) with a microgrid, each with distinct characteristics and control strategies impacting microgrid operation. A grid-forming inverter, also known as a voltage-source inverter (VSI) operating in voltage control mode, is capable of independently establishing and maintaining the voltage and frequency of an AC microgrid. It acts as an ideal voltage source, providing the voltage and frequency reference for other devices within the microgrid to synchronize with. Grid-forming inverters are essential for islanded operation, where the microgrid is disconnected from the main grid, as they are responsible for creating a stable and reliable AC power supply. Control strategies like droop control or virtual synchronous generator (VSG) control are typically employed to enable grid-forming inverters to regulate voltage and frequency and share load proportionally among multiple inverters. A grid-following inverter, also known as a current....