Input-to-output stability analysis of interconnecting microgrids

This paper proposed a new methodology to analyze the stability of interconnected systems, which is based on input-to-output stability (IOS) theory. The corresponding application in microgrids is also discussed. First, the local IOS (LIOS) theorem is presented. Second, one typical interconnecting microgrid is presented and the input-to-output gain of each subsystem is calculated according to its electrical model. Finally, by considering voltage and current as input and output, the LIOS theorem is applied to the stability judgment of this microgrid after lock-rotor motor access and is tested by physical experiment. The result shows that the LIOS theorem can serve as a criterion for an interconnected system´s stability analysis and has promising application prospect in system design, operation auxiliary decision making and emergency control.