A Novel Reliability Assessment Method for Radial Power Networks With Multiple (Backup) Power Sources and Tie Lines

Reliability assessment is crucial for modern electricity system, particularly in mission-critical scenarios such as hospitals, data centers and great event venues. For these scenarios demanding critical power supply assurance, the accuracy of reliability assessment holds paramount importance, followed by efficiency. Whereas, traditional failure mode and effect analysis methods (FMEA), characterized by its deterministic logic and accurate assessment, face significant limitations in addressing multi-source configurations with backup power units and reconfigurable tie lines. This paper proposes a graph-theoretic framework integrating Floyd-Warshall algorithms to address these limitations. The methodology systematically analyzes fault isolation, impact propagation, and restoration pathways through four key steps: (1) fault zone classification via matrix-based approach, (2) post-fault bus state analysis via adaptive adjacency matrices, (3) prioritized tie line restoration, and (4) backup power sources activation. The proposed method's efficacy is validated via a case study conducted on a 10-bus radial multi-source power network. The results exhibit strong alignment with ETAP simulations and effectively quantify the synergistic effects of multi-source coordination, backup power utilization, and tie-line restoration capabilities, making the method particularly advantageous for complex radial power network scenarios.