Objective Existing brittle source identification methods have such problems as their single-perspective approach, disregard for the local and global characteristics of nodes, and insufficient consideration of the loads carried by nodes.

Methods The method proposed herein identifies the inherent brittleness of the ship power system as the root cause of interruption and chain collapse. To establish a brittleness index, the method first considers node degree, eigenvector centrality, node cohesiveness, closeness centrality and brittle electrical betweenness from a brittleness perspective based on complex network theory. The combinatorial intuitionistic fuzzy analytic hierarchy process (IFAHP）and entropy weight method (EWM) with the Nash equilibrium as the coordination objective. The five indexes are then combined through comprehensive assignment to obtain a comprehensive brittleness index. Finally, the proposed brittle source identification method is validated using a typical four-station annular ship grid.

Results The method identifies four levels of brittle sources based on the network efficiency of different brittleness indexes, and the results demonstrate its ability to identify brittle sources more comprehensively and reasonably.

Conclusion The results of this study can provide effective guidance for the prevention and control of inter-locking faults in ship power networks.