This paper presents the control of power sources by lookup table controller to maintain the voltage of critical load and to prevent the collapse of a mixed-source DC microgrid which consists of grid, diesel generators, batteries and solar cells that connect to DC bus. MATLAB is used to a simulation of the microgrid system. The experiment presents the time comparison of four types of switches including magnetic contactor, relay, solid-state relay and power MOSFET which can maintain DC bus voltage in a specified range which least effects to critical load operation. Finally, applied in the data center system of a small factory which has satisfactory results.
