Implementation of Differential Algorithm for Busbar Protection
Faults in power systems are classified as internal and external faults. Faults within the zone are termed as internal faults whereas; the faults outside the Zone are called as external faults. Ideally, a relay outward after the protection of a zone should operate only for internal faults. It should restrain from operating for external faults or through faults. In this project, the busbar protection using differential protection scheme has been investigated for internal and external faults. The current magnitude from the Current Transformer is compared with a preset value and when the current exceeds the preset value, and then a trip command is given to associated circuit breaker. In this work, an algorithm has been developed to improve the selectivity of the relay and the same is tested on three-phase bus bar having two incoming lines and three outgoing lines at different fault levels and the results are verified for internal and external faults. The entire algorithm is programmed and graphical views of relay performance are verified using the MP LAB platform.
Kleber M. Silva, Alfredo Miguel P. Escudero, Felipe V. Lopes and Flavio B. Costa, June 2018, “A wavelet – Based Busbar Differential Protection”, IEEE transactions on power delivery, Vol 33, No. 3, June 2018.
Mohindar S.Sachdev, Life Fellow, S. Sidhu, Harjeet Singh Gill, July 2000, “A Busbar Protection Technique and Its Performance During CT Saturation and CT Ratio-Mismatch”, IEEE transactions on power delivery, Vol. 15, No. 3, July 2000.
Y.C. Kang, J.S. Yun, B.E. Lee, S.H. Kang, S.I. Jang and Y.G. Kim, “Busbar Differential Protection in Conjunction with a Current Transformer Compensating Algorithm”, IET Generation Transmission Distribution ,2008, 2, (1),pp. 100-109.
Yong-Cheol Kang, Ui-Jai Lim, Sang-Hee Kang, Peter A. Crossley, April 2005, “A Busbar Differential Protection Relay Suitable for Use with Measurement Type Current Transformer”, IEEE transactions on power delivery, Vol. 20, No. 2, April 2005.
Cesareo Fernandez, October 2001, “An Impedance– Based CT Saturation Detection Algorithm for Bus-bar Differential Protection”, IEEE transactions on power delivery, Vol. 16, No. 4, October 2001.