A New Real-Time Fast Discrete S-Transform for Cross-Differential Protection of Shunt-Compensated Power Systems

• Published in: IEEE transactions on power delivery Vol. 28; no. 1; pp. 402 - 410
• Main Authors: Krishnanand, K. R., Dash, P. K.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2013; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Change detection; Computation; cross-differential protection; Discrete Fourier transforms; Energy use; fast discrete S-transform; Feasibility; Hardware; Microprocessors; On-line systems; Power systems; Power transmission; Real-time systems; Relaying; Time domain analysis; Time frequency analysis; TMS320C6713; Transforms; transmission lines
• ISSN: 0885-8977; 1937-4208
• DOI: 10.1109/TPWRD.2012.2221749

This paper presents a cross-differential protection scheme for power transmission systems inclusive of a STATCOM. The measurement of the energy of the prominent frequency components of the current signals is done using a computationally fast version of the discrete S Transform suitable for power system signal analysis. The energy thus obtained is used for cross-differential purposes. The practical implementation of the new fast discrete S-transform is performed on the TMS320C6713 digital signal processor for verification of real-time operation of the relaying scheme. The computational load of the processor to perform the transform in online mode is reduced by a cross-differential check using a cumulative difference technique. The results obtained from the extensive experimentations show the feasibility and speed of the new approach.