A new smart distribution grid fault self-healing system based on traveling-wave

Considering painful lessons caused by large scale blackouts at home and abroad, building a smart distribution grid fault self-healing system is of great urgency. Fast and accurate fault location is the key technology of self-healing, therefore, a new smart distribution grid self-healing system based on traveling-wave is proposed to greatly reduce users´ outage time and range, which consists of three parts: fault detection, fault location, fault isolation and power service restoration. The fault detection is based on secondary side traveling-waves of voltage transformer. A fault is identified when the first measured traveling-wave is greater than the setting threshold. The fault location is based on multi-terminal traveling-wave arriving time. Fault distance is calculated precisely via the least square fitting result. Afterwards faults of distribution grid, which are distinguished, can be isolated intelligently. Extensive simulative and experimental results demonstrate that the accuracy and self-healing speed of the proposed system is significantly improved and “Seamless self-healing” is expected to achieve.