Research on a fast self-healing control method for tie-line faults in regional distribution networks based on...

To address the challenges of islanding susceptibility, complex network topology, and insufficient coordination between traditional protection and stability control under high penetration of distributed generation in regional distribution networks, a fast fault self-healing control method based on source-load-storage coordinated interaction is proposed. The frequency and voltage dynamic characteristics of regional distribution networks after disconnection from the main grid are systematically analyzed, revealing the relationship between tie-section power exchange and island stability. A full-process fast self-healing framework is established, covering fault isolation, island detection, stable control, and grid reconnection, along with a master-slave self-healing architecture enabling multi-level information sharing and coordinated decision-making. To cope with the difficulty of accurate island identification caused by variable topology, an island detection method based on a pruning-optimized search strategy is developed, improving real-time performance by eliminating unnecessary low-voltage branches. A circuit breaker position fault-tolerant mechanism based on enumeration and current criteria enhances robustness against switch status anomalies. For island stability control, a "regulation-priority with regulation-shedding coordination" principle is adopted, prioritizing rapid regulation of distributed resources such as energy storage and photovoltaics. Simulation and field tests show that the proposed method reduces recovery time by over 50% (from 6.8 s to 3.2 s), limits frequency deviation to 0.15 Hz, and decreases load loss to 12%, compared with conventional load shedding strategies. These results verify the method's effectiveness, robustness, and practical applicability for real-time full-process dynamic self-healing in regional distribution networks.