Document Type : Original Research Paper
Authors
Power Engineering Department, Faculty of Electrical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran.
Abstract
Background and Objectives: Protection of sub-transmission systems requires maintaining selectivity in the combinatorial scheme of distance and direction overcurrent relays (DOCRs). This presents a complex challenge that renders the need for a robust solution. Thereby, the objective of the present study is to decrease the number of violations and minimize the tripping time of relays in this particular issue.
Methods: This study deals with this challenge by using numerical DOCRs which follow non-standard tripping characteristics without compromising the compatibility of the curves. In this process, the time-current characteristics of relays are described in such a manner that they can maintain selectivity among themselves and with distance relays. Therefore, in addition to the second zone timing of distance relays, time dial settings, and plug settings of overcurrent relays, the other coefficients of the inverse-time characteristics are also optimized. The optimization procedure is formulated as a nonlinear programming model and tackled using the particle swarm optimization (PSO) algorithm.
Results: This approach is verified by applying on two test systems and compared against conventional methods. The obtained results show that the proposed approach helps to yield selective protection scheme owing to the provided flexibility.
Conclusion: The research effectively enhanced selectivity in sub-transmission systems and minimizing relay tripping times through the innovative use of numerical DOCRs and PSO-based optimization.
Keywords
- Coordination Violations
- Nonlinear Programming Model
- Combinatorial Protection
- Selectivity
- Distance Protection
Main Subjects
Open Access
This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit: http://creativecommons.org/licenses/by/4.0/
Publisher’s Note
JECEI Publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Publisher
Shahid Rajaee Teacher Training University
Send comment about this article