Phase-Space-Based Fault Detection in Distance Relaying

This paper proposes an effective fault detection technique in distance relaying using phase space. This is based on an embedding theorem which shows that a time series can be mapped to a higher dimensional space called phase space through embedding. Thus, a sampled signal can be transformed in to the phase space so that its features can be more clearly viewed. The original signal is decoupled into two parts as: normal and disturbance part. The fault detection is easily achieved as the disturbance part of the signal produces an irregular shape compared to the shape produced from the normal part of the signal. The fault detection signal using phase space (FDPS), derived from phase-space transformation, effectively detects the faults in the transmission line with wide variations in operating conditions. The results from an extensive study indicate that the proposed FDPS can reliably detect the faults in distance relaying.