Integrating multiple clusters of grid-forming inverters to form a consolidated grid after a blackout is pivotal to increase the reliability and stability of the grid in the presence of renewable energy sources. However, due to the high number of grid-forming inverters serving loads, the integration of the grid-forming inverter clusters while considering each cluster’s constraint on frequency and rate of frequency change (ROCOF) is complex and time-consuming. In this digest, a generalized method to integrate the clusters of grid-forming inverters that consider the constraints on ROCOF and frequency change is presented. In the proposed control scheme, the master cluster is selected through constrained optimization to ensure the lowest integration process while observing the frequency and ROCOF constraints. Afterward, all the grid-forming inverter clusters will start to integrate with the master cluster until all the grid’s clusters get consolidated. A summary of the simulation and experimental results is presented to validate the impact of the proposed scheme on reducing the integration time of the grid-forming clusters.
