Vol. 1 No. 2 (2019): Volume 1, Issue 2, Year 2019

Implementation of Differential Algorithm for Busbar Protection

Bharath Kumar Sugumar
PG Scholar, Department of Electrical Engineering, Government College of Technology, Coimbatore, TN, India
Sujatha Balaraman
Associated Professor, Department of Electrical Engg, Government College of Tech, Coimbatore, TN, India
Published March 25, 2019
  • Busbar protection,
  • CT saturation,
  • Ratio mismatch of CT secondary,
  • Works on busbar protection,
  • Numerical relay
How to Cite
Sugumar, B. K., & Balaraman, S. (2019). Implementation of Differential Algorithm for Busbar Protection. International Research Journal of Multidisciplinary Technovation, 1(2), 150-157. Retrieved from https://mapletreejournals.com/index.php/irjmt/article/view/224


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.


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