As an effective interface for renewable energy integration

microgrids have attracted more and more attention. Most of the distributed energy sources in the microgrid should be grid-connected by inverters

but unlike synchronous generators

traditional inverter control algorithms only consider the rapid response with no inertia. In order to solve this problem

the virtual synchronous generator (VSG) control strategy in support of the stable operation of microgrids is summarized. Then the VSG control algorithm of adaptive virtual rotor inertia is proposed by referring to the physical meaning of the synchronous generator rotor inertia and power angle curve. Following an analysis on the small-signal model for the VSG-oriented distributed generator

the selection principle of adaptive inertia coefficients is presented. Finally

the proposed algorithm is verified by simulation results based on a PSCAD/EMTDC microgrid model. This work is supported by National High Technology Research and Development Program of China (863 Program) (No. 2011AA050204) and National Natural Science Foundation of China (No. 50907060).