ew 14(3): e5

Research Article

A New GPS-based Digital Protection System for Smart Grids in Loop Structure

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  • @ARTICLE{10.4108/ew.1.3.e5,
        author={X. Liu and M. Steurer and M. Yu},
        title={A New GPS-based Digital Protection System for Smart Grids in Loop Structure},
        journal={EAI Endorsed Transactions on Energy Web},
        volume={1},
        number={3},
        publisher={ICST},
        journal_a={EW},
        year={2014},
        month={12},
        keywords={Smart grid protection, differential protection, GPS synchronization, and microcontrollers.},
        doi={10.4108/ew.1.3.e5}
    }
    
  • X. Liu
    M. Steurer
    M. Yu
    Year: 2014
    A New GPS-based Digital Protection System for Smart Grids in Loop Structure
    EW
    EAI
    DOI: 10.4108/ew.1.3.e5
X. Liu1,*, M. Steurer1, M. Yu2
  • 1: FSU, Center for Advanced Power System, 2000 Levy Ave, Tallahassee, FL 32310
  • 2: FSU, Dept. of ECE, 2525 Pottsdamer Street, Tallahassee, FL 32310
*Contact email: xliu@caps.fsu.edu

Abstract

This paper presents a new digital protection system to solve the protection challenges in future smart grids, i.e., fast protection and fault isolation in a loop-structured system with limited magnitude of fault current. The new system combines two protection algorithms, i.e., a differential protection as the primary algorithm and an overcurrent protection as the backup one. The new system uses real-time Ethernet and digital data acquisition techniques to overcome the restriction on data transmission over large grids. The current measurements at different locations are time-synchronized by GPS clocks, and then transmitted to a central computer via the Ethernet. As opposed to digital relays which often contain PMU functionality nowadays, this approach uses time stamps on the instantaneous current values. We build a prototype of the new system on a test-bed. The results from simulations and experiments have demonstrated that the protection system achieves fast and accurate protection.