Various Structures and Control Strategies for Provisional Energy Transaction Management in Coupled Microgrid Clusters

An autonomous microgrid (MG) may observe overloading and renewable-based excessive generation. Such issues can lead to unacceptable deviation in the MG's voltage or frequency. These problems can be eased by load-shedding or renewable curtailment. On the other hand, forming provisional neighboring MG clusters and facilitating power exchange among them can also improve the situation more economically and effectively. The power exchange link between the MGs can be in the various forms such as a three-phase ac, a single-phase ac or a dc link. This approach requires power electronics-based converters to interlink the three-phase ac microgrid with the power exchange link and control the power-sharing amongst them. This paper has studied such structures and has proposed a decentralized approach to control the converters of the neighboring MGs to enable power-sharing amongst them. The performance of the proposed control mechanisms is evaluated through simulation studies in PSIM®.