A centralized controller of DC microgrid based on model predictive method is proposed in this paper. Stable and economical operation of the microgrid is guaranteed to provide high quality power for load by generating reference signals for local controller utilizing model predictive method. In addition, local droop control is switched on in case of communication failure to provide redundant reference signal choice. To verify the effectiveness of the proposed model predictive control system, simulations are conducted on MATLAB with results showing that the control objectives are fulfilled in both grid-connected and islanded mode with economical and flexible operation during normal condition using the proposed centralized controller and safe operation during communication failure by switching to the alternate local droop control.