I. Introduction
Microgrid is a power distribution system integrating distributed generators (DGs), energy storage systems (ESs) and controllable loads [1], [2]. An MG can work in a grid-connected mode or an islanded mode. A smart MG is distinguished from the traditional distribution systems in terms of reliability, self-adequacy, self-healing, and interactive characteristics [3]. According to recent studies in [2]–[9], connecting multiple MGs to form a power system can further improve the system operation and reliability thanks to the salient features of networked MGs such as coordinated energy management and interactive support and exchange.