Statistical Analysis of Protection Current Transformer Performance Based on Error Ratio and Knee Voltage on 20 kV Feeder at Bangka Transmission and Substation Service Unit
DOI:
https://doi.org/10.33019/jurnalecotipe.v12i1.4558Keywords:
Current Transformer, Knee Voltage, Protection System, Statistical Analysis, Ratio ErrorAbstract
Current Transformers (CTs) are essential components in power system protection, ensuring accurate current measurement for relay operations.. This study evaluates the accuracy of protection CTs used in 20kV feeders at the Bangka Transmission and Substation Service Unit. Measurements were conducted on CTs with 5 and 7 years of usage to analyze ratio error and knee voltage compliance with IEC 61869-2 standards. The results indicate that all CTs meet the standard, with ratio errors below 1% and knee voltages exceeding 60V. Normality tests confirmed that the data are normally distributed, allowing statistical analysis using t-tests. The t-test results showed no significant difference in ratio error and knee voltage between CTs used for 5 and 7 years. This study concludes that aging over this period does not significantly affect CT accuracy, ensuring continued reliability in power system protection.
Downloads
References
Harlow, J. H. Electric Power Transformer Engineering. New York: Marcel Dekker, 1998.
Gurevich, V. Instrument Transformers: Theory, Applications, and Testing. New York: Wiley, 2003.
Divan, D. M. "Transient Performance of Current Transformers." IEEE Transactions on Power Delivery, Vol. 12, No. 3, pp. 1103–1111, July 1997.
Gurevich, V., Instrument Transformers: Theory, Applications, and Testing., New York : Wiley, 2003.
Slemon, G. R. "Evaluation of the Accuracy of Protection CTs Under Fault Conditions." IEEE Transactions on Power Delivery, Vol. 14, No. 4, pp. 1234–1242, October 1999
Smith, J., Brown, L., & Patel, R. "Analysis of Current Transformer Saturation and Its Impact on Protective Relay Performance." IEEE Transactions on Power Delivery, vol. 33, no. 3, pp. 1234–1243, 2018.
Kumar, A., Zhang, Y., & Lee, S. "Modeling and Simulation of CT Saturation Effects in Digital Relaying." IEEE Transactions on Power Delivery, vol. 34, no. 4, pp. 5678–5686, 2019.
Wang, X., Li, Y., & Chen, F. "A Study on Knee-Point Voltage and Its Impact on Current Transformer Performance During Fault Conditions." IEEE Transactions on Power Delivery, vol. 37, no. 4, pp. 1895–1904, 2022.
Chen, Z., Li, Y., & Smith, M. "Impact of Accuracy Limit Factor on Protection CT Performance in High Fault Currents." IEEE Transactions on Power Delivery, vol. 36, no. 2, pp. 700–708, April 2021.
Kumar, H., Patel, A., & Zhang, J. "Evaluation of Safety Factor in Current Transformers for Reliable Protection Systems." IEEE Transactions on Instrumentation and Measurement, vol. 70, no. 5, pp. 1–8, May 2022.
Wang, L., Zhang, H., and Lee, S. “Assessment of Burden Effects on Current Transformer Accuracy Under High Fault Conditions.†IEEE Transactions on Power Delivery, vol. 37, no. 3, pp. 1120–1127, July 2022.
Gurevich, V., Instrument Transformers: Theory, Applications, and Testing, New York : Wiley, 2003.
International Electrotechnical Commission. IEC 61869-2: Instrument Transformers – Part 2: Current Transformers. Geneva: International Electrotechnical Commission, 2010.
Montgomery, D. C., Design and Analysis of Experiments (9th ed.), New York : Wiley, 2017.
Downloads
Published
Issue
Section
License
Copyright (c) 2025 Jurnal Ecotipe (Electronic, Control, Telecommunication, Information, and Power Engineering)
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright in each article is the property of the author.
- The author acknowledges that the Jurnal Ecotipe (Electronic, Control, Telecommunication, Information, and Power Engineering) has the right to publish for the first time with a Creative Commons Attribution 4.0 International License.
- The author can enter the writing separately, regulate the non-exculsive distribution of manuscripts that have been published in this journal into other versions (for example: sent to the author's institution respository, publication into books, etc.), by acknowledging that the manuscript was first published in the Jurnal Ecotipe (Electronic, Control, Telecommunication, Information, and Power Engineering);
