Droop control strategy in inverter‐based microgrids: A brief review on analysis and application in islanded mode of operation

Abstract

Droop control is at the first level of the control hierarchy and does not require communication. Having high reliability, is usually used in inverter‐based microgrids. The microgrid can operate as an island, and it can also be connected to the main or auxiliary grid. By reviewing the extensive literature on the role of the controller in inverter‐based microgrids for the island mode of operation, in this study, the droop regulation strategy has been covered briefly and compactly. Droop regulation is an example of decentralized regulation in basic control, and its importance is revealed in the island mode of operation when it is possible to share power in all facilities without needing to communicate with other units. Disadvantages of common droop control, such as slow transient dynamics and low energy quality for non‐linear and unbalanced loads, have limited its use in advanced microgrids. Therefore, various methods to improve the common droop control have been investigated so far, some of which have been mentioned. This study highlights the application of droop control strategies in order to coordinate distributed generation units in the microgrid. About 180 published studies in this field have been reviewed, classified and indexed for quick reference.