Abstract: The microgrid clusters based on flexible back-to-back converter（BTBC）interconnection can realize the power decoupling control between different microgrids. The power interaction between microgrids is more flexible than that based on impedance interconnection. However, the power control strategy for BTBC interconnection under disturbance and its influence on system stability are still unclear. This paper establishes a full-order small disturbance model of interconnected microgrids based on BTBC. The links related to stability in the low frequency band are obtained through participation factor analysis. And the dominant modes related to power interaction are obtained. The influence of interconnected power control on system stability is analyzed. On this basis, an active power exchange control strategy of flexible interconnected microgrids is proposed to reduce the impact of disturbance on the local stability of microgrids. The small-signal stability of the system with this strategy is analyzed by using the root locus. And the effectiveness of the strategy is verified by simulation platform.