Adaptive Cumulative Sum-Based Fault Detector for Transmission Lines

Adaptive Cumulative Sum-Based Fault Detector for Transmission Lines

In this paper a novel approach is proposed for fault detection in transmission system. This idea is based on a cumulative sum-based method (CUSUM) whose structure is improved to become adaptive with the line current passed through. Although the CUSUM-based fault detector performance is good in both aspects of security and dependability, in fault condition with high fault resistance in transmission system, its indices cannot detect the fault. The proposed adaptive CUSUM (ACUSUM) algorithm can detect high resistance faults and distinguish them from normal condition or load changing. By using the proposed method, just a few milliseconds after high impedance fault inception, the fault detection unit (FDU) permits the main protection algorithm to become activated. The results have shown that the proposed method has good performance in speed and accuracy.