A novel traveling-wave-based detection and self-healing approach for series faults in smart grids under renewable...

Conventional protective devices cannot reliably detect series faults at the far end of the distribution feeder, such as open-conductor faults, downed conductor faults from the load side, and downed conductor faults from the source side when associated with high-impedance conditions. This limitation is especially challenging in the presence of distributed generation units. This paper introduces an innovative scheme for detecting series faults using traveling wave voltage measurements. This scheme identifies faults by comparing the polarities of the first-arriving voltage waves at the lateral ends. During such faults, the polarity at the lateral end downstream of the fault differs from the others. Building on this principle, a fault management scheme is proposed that combines polarity differences with a two-terminal traveling-wave scheme to both locate the fault and restore service. The scheme is validated on the IEEE 33-bus system using PSCAD simulations. The results confirm that the proposed scheme is sensitive to all types of series faults, whether or not distributed generation (DG) units are connected, and remains secure under normal operating conditions such as load switching and capacitor bank connection. Furthermore, the scheme accommodates the uncertainty inherent in renewable energy sources, making it effective across the full range of power contributions-from zero (when disconnected from the grid) to full output. The results confirm that proposed scheme provides high reliability in detecting the open-conductor faults and identifying faulted laterals regardless of synchronization misalignment between measurement points. It accurately determines the faulted section for synchronization deviations up to 3 µs, while deviations exceeding 1 µs may affect accuracy under busbar fault conditions. A verification step using fault indicators at secondary substations ensures correct section isolation even under significant synchronization deviations. Overall, the proposed algorithm outperforms existing methods, particularly in networks with DG units.