A new time–frequency approach for distance protection in parallel transmission lines operating with STATCOM

• Published in: International journal of electrical power & energy systems Vol. 61; pp. 606 - 619
• Main Authors: Dash, P.K., Moirangthem, Joymala, Das, Sahasranshu
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.10.2014; Elsevier
• Subjects: Applied sciences; Change detection; Classification; Computation; Connection and protection apparatus; Cross-differential protection; Disturbances. Regulation. Protection; Electrical engineering. Electrical power engineering; Electrical power engineering; Energy use; Exact sciences and technology; Fast discrete S-Transform; Fault classification and location; Faults; Filtering; Filtration; Interpolation; Parallel transmission lines; Power networks and lines; Static Compensator (STATCOM); Testing. Reliability. Quality control; Transforms; Cross-differential protection; Static Compensator (STATCOM); Parallel transmission lines; Change detection; Fast discrete S-Transform; Fault classification and location; Flexible AC transmission systems; Differential protection; Discrete transformation; Protective device; Parallel; Damage prevention; Implementation; Interpolation; Transmission line; Static reactive compensator; Parallel system; Spectral energy; Classification; Defect localization; On line processing; Impedance; Distance protection; Defect detection
• ISSN: 0142-0615; 1879-3517
• DOI: 10.1016/j.ijepes.2014.04.011

[Display omitted] •A novel fast discrete S-Transform is presented for cross differential and impedance protection.•The new variant provides fast fault classification and location in the presence of STATCOM.•Spectral energy changes can be calculated in real time.•Identification of faulted section before or after STATCOM is presented. The paper presents a new cross-differential and impedance protection scheme for a parallel transmission system, in the presence of STATCOM. A cumulative sum (CUSUM) approach is used for fault detection by obtaining the measured values of currents in the two lines. Spectral energies of the current signals are then computed by using a new fast discrete S-Transform (FDST) approach for classification of the nature of faults on the lines. The modified transform is based on new scaling, band pass filtering, and interpolation techniques that makes the new variant computationally much faster than the earlier S-Transform and can be implemented in real time. Further the FDST is used to accurately identify the occurrence of the fault before or after the STATCOM and compute the location of the fault using one half cycle data prior to the occurrence of the fault and one half cycle data after the fault has occurred.