AC/DC hybrid distribution can accept distributed power supply and DC load more easily and can alleviate the contradiction between the restricted space of city grid site and the high density of load. Thus it has become an important development trend of modern city distribution network. After access to the flexible AC and DC devices, distribution network has changed to a multi terminal power network from a single terminal power network, thereby its reliability will face to new challenges. This paper summarizes the fault characteristics of AC/DC hybrid power distribution system, analyzes the influence of the flexible DC control device on the flexible side and the system side, and then proposes a cooperative control architecture of the time sequence cooperative smart device. It combines fault characteristics of AC/DC hybrid power system, uses the fast response characteristics of flexible power electronic devices, and designs the protection and control strategy of flexible DC control device and AC protective control device. By using GOOSE directed node and fast communication mechanism and applying protection and control coordination strategy for fault location and isolation, it effectively enhances the reliability of AC/DC hybrid distribution with flexible interconnection device, thus it has practical value in engineering. This work is supported by National High-tech R & D Program of China (863 Program) (No. 2015AA050102).