To improve the reliability of an MMC series structured microgrid system, a micro-source dynamic redundancy control strategy based on Ensemble Empirical Mode Decomposition (EEMD) is studied. The system is introduced to realize micro-source dynamic redundancy control through three steps: micro-source original power EEMD decomposition, generation module selection, and control signal expansion and distribution during non-fault operation; when the system is in fault operation, the faulty generation module is removed first, and then operated according to the non-fault operation state. Finally, taking all generation modules of the upper bridge arm of phase A as an example, it is verified that the strategy can not only realize microsource dynamic redundancy control, but also can improve the utilization rate of microsources. At the same time, the output voltage when the generation module is in the system with and without redundancy is simulated and analyzed, and the results prove the reliability and effectiveness of the proposed dynamic redundancy control strategy. This work is supported by the National Natural Science Foundation of China (No. 51967011).