The integration of various distributed energy sources into a power system requires special grid topology and control system structure. The power system considered is a hybrid microgrid comprising DC and AC subsystems with a possibility to control the generation and load in both subsystems. To achieve the required microgrid performance characteristics, it is proposed to use a frequency adjusting controller with optimized parameters, which maintains the electric operation modes in both subsystems with the preset droop. The controller is connected to a bidirectional converter that controls the redistribution of power between the grid AC and DC sides. In addition, for islanding the DC subsystem for isolated operation, an appropriate function has been implemented at the microgrid control system upper level. The islanding of the DC system for isolated operation is necessary to prevent the storage batteries from becoming discharged and to protect the critical loads on the DC side. Owing to the proposed microgrid control algorithm implemented in the controller, stability of the AC subsystem is maintained during its joint operation with the DC subsystem. The operation modes with islanding the DC subsystem for isolated operation have been analyzed, and the effectiveness of the proposed control system has been evaluated.