Masters Theses
Abstract
"Schweitzer Engineering laboratories (SEL) donated the SEL 387, SEL 311L, and SEL 351S relays and the SEL AMS to Missouri University of Science and Technology. This thesis documents the demonstration approach to set the SEL 387 relay to protect a grounded wye-grounded wye transformer and then test these settings by injecting fault currents into the relay using the SEL AMS. This thesis explains the approach to set the differential element of the SEL 387 relay to protect a transformer against internal faults and the overcurrent element of the SEL 387 relay to protect transformer against external faults. A radial power system model is assumed and modeled using ASPEN Oneliner and Power Flow software. Fault currents obtained from ASPEN model are injected to the relay using the SEL AMS. Separate tests are performed for the differential element and the overcurrent element. The objective of testing the differential element is to show that it is tripping for internal faults and restraining for external faults. The approach used by the SEL 387 differential relay to make trip decisions is theoretically calculated. These theoretical results are verified with results obtained from the relay fault event reports. The instantaneous and time overcurrent elements are tested by running various types of faults at four different locations. The objective of testing the overcurrent elements is to show that the instantaneous overcurrent elements are tripping only for transformer primary side faults and to show that primary side time overcurrent element is coordinating with the secondary side time overcurrent element"--Abstract, page iii.
Advisor(s)
Crow, Mariesa
Committee Member(s)
Shamsi, Pourya
Joo, Jhi-Young
Department(s)
Electrical and Computer Engineering
Degree Name
M.S. in Electrical Engineering
Publisher
Missouri University of Science and Technology
Publication Date
Fall 2016
Pagination
xiv, 142 pages
Note about bibliography
Includes bibliographical references (pages 140-141).
Rights
© 2016 Aamani Lakkaraju
Document Type
Thesis - Open Access
File Type
text
Language
English
Subject Headings
Electric transformers -- TestingProtective relaysElectric relaysElectric power distribution
Thesis Number
T 11036
Electronic OCLC #
974715141
Recommended Citation
Lakkaraju, Aamani, "Protection of a 138/34.5 kv transformer using SEL 387-6 relay" (2016). Masters Theses. 7606.
https://scholarsmine.mst.edu/masters_theses/7606