A Localized Distribution Line Protection Method for Fast Fault Isolation and System Restoration

The distribution system directly serves electricity users and is a crucial link in ensuring stable, reliable, and high-quality power supply. In distribution line operation, if faults are not handled properly, large amount of time and manual efforts will be taken to isolate and repair the faulted area, resulting in low electricity reliability and long outage time. This article proposes an innovative distribution line fault isolation and system recovery scheme that utilizes electrical signal spatio-temporal characteristics generated by breaker operation and is based only on local information. By isolating the fault from both ends, this protection scheme also lays the foundation for restoring power supply to the un-faulted section. With the function of one-side voltage-loss triggered closing for the distribution network tie breaker, the protection scheme achieves power supply restoration to un-faulted sections. Furthermore, by distinguishing between transient faults and permanent faults, the protection scheme further optimizes the control of the tie breakers, reducing the negative impact on device lifespan brought by the fault recovery processes in traditional local automation schemes.