Online Dynamic Security Assessment of Microgrid Interconnections in Smart Distribution Systems

This paper studies the online dynamic security assessment (DSA) of future distribution systems in which multiple electrically coupled microgrids are operated as an interconnection. By leveraging the highly controllable power-electronics-based interfaces, we propose a novel interface control strategy for desirable load sharing among interconnected microgrids. Under such a control framework, theoretical results on system-wide stability criteria in the sense of Lyapunov are obtained. Potential application of these results for microgrid-based smart distribution system DSA is presented. Minimum information exchange is required among microgrid modules and the distribution system operator, which is a highly desirable feature in future distribution management systems. Numerical studies of a five-microgrid study system designed based on the IEEE 123-node test feeder show the effectiveness of the proposed control strategy and DSA framework.