A Sensitivity-Based Regulation Method for Tie-Line Power of AC Microgrid Cluster

The microgrid cluster (MGC) system can improve distributed power utilization by interconnecting energy between microgrids in the cluster through tie-line. However, there is a security region for tie-line. When the tie-line power exceeds the limit, it would affect the safe and stability operation of the system. In this paper, we investigate the tie-line power regulation strategy of AC MGC that allows the tie-line power to reach the expected value. First, a centralized MGC operation architecture is built, and the direct control devices within the MGC are identified. Then, considering the diesel generator economic operation interval constraints, a sensitivity-based tie-line regulation strategy is proposed. In the strategy, the sensitivity of the output power of different devices to the power of the tie-line needs to be fitted in advance. Finally, different energy storage SOC state scenarios are set up for arithmetic simulation to verify the effectiveness of the strategy. The strategy enhances the level of control over MGC.