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In an isolated DC microgrid consisting of photovoltaic cells, an energy storage unit and load, reasonable control of grid-connected two-way AC/DC converter can effectively realize coordinated power distribution and bus voltage stabilization of the microgrid. A mathematical model of grid-connected converter was established first in this paper, followed by a simulation analysis of the grid-connected converter under direct voltage control. In consideration of the fact that the ideal dynamic voltage response could not be realized by conventional control of the grid-connected converter, a seamless switching control strategy of inhibiting voltage fluctuation was proposed based on the voltage fluctuation analysis of the AC/DC converter, which improved the robust stability of the DC microgrid. The effectiveness and feasibility of the proposed control strategy were verified through the simulation results.