When a serious fault disturbance occurs due to a three-phase short circuit in an AC/DC hybrid microgrid, the system protection device cuts off the normal power supply to the fault protection non fault area. Due to the large power impact on the system caused by the topology change and the small capacity of the islanded microgrid, its ability to cope with fault disturbances is limited. Therefore, it is unknown whether the islanded AC/DC hybrid microgrid system can restore short-term voltage stability after the network topology is changed due to fault removal. This article considers the system topology changes caused by the topology change and uses the extended theorem of mixed potential functions to analyze the large signal stability of AC/DC hybrid microgrid systems. The proposed criteria provide the maximum disturbance power limit required for voltage stability in AC/DC hybrid microgrids after the topology change. At the same time, the impact of system parameters Kip, L1, Cdc, and RS on the system’s temporary stability is analyzed by establishing a post fault system stability domain. The proposed criteria are of great significance for improving the voltage stability of AC/DC hybrid microgrids after three-phase short-circuit faults. Finally, the correctness of the proposed method was verified through experiments.