Unified DFIG Control Strategy for Stability Support and Coordinated Power Export in Microgrid Clusters

This paper investigates AC microgrid clusters with high penetration of DFIG-based wind power. Conventional separated control of wind power output and stability support may cause abrupt power command variations during transitions between grid-connected and islanded operating modes, thereby aggravating system power imbalance. To address this issue, a unified DFIG control strategy is proposed in which an operating objective coordination factor continuously coordinates stability support and wind power output within a unified reference generation framework. A continuity preservation mechanism is then developed to suppress transient impacts through phase angle coordination and DC link power correction. Simulation results show that, compared with conventional MPPT + PQC and FSC methods, the proposed strategy mitigates transition induced fluctuations during grid island transitions. RTDS experiments based on a modified Banshee microgrid model further verify that the proposed strategy improves system stability during grid-connected to islanded transition and islanded to grid connected reconnection.