Title: Optimal coordination of dual-setting DOCRs for common operating mode of microgrid using mixed characteristics
Authors: Priyanshul Niranjan; Niraj Kumar Choudhary; Nitin Singh; Ravindra Kumar Singh
Addresses: Department of Electrical Engineering, MNNIT Allahabad, Prayagraj, India ' Department of Electrical Engineering, MNNIT Allahabad, Prayagraj, India ' Department of Electrical Engineering, MNNIT Allahabad, Prayagraj, India ' Department of Electrical Engineering, MNNIT Allahabad, Prayagraj, India
Abstract: The microgrid's operating modes significantly impact the relay coordination schemes. The relay coordination schemes with conventional directional overcurrent relays (DOCRs) using standard relay characteristics are not always efficient. This study proposes an optimal relay coordination scheme using different characteristics curves for dual setting DOCRs (DS-DOCRs). A third decision variable known as curve setting has been considered along with the plug setting and time dial setting for each DS-DOCR. The novel contribution of this study is to determine the optimal settings of DS-DOCRs that is common for both grid-connected and islanded modes. The proposed protection coordination scheme has been formulated as mixed-integer nonlinear programming problem (MINLP) and optimally solved using genetic algorithm (GA). The performance of GA has been compared with firefly algorithm and simulated annealing. Detailed simulation studies of the proposed scheme are carried out on 7-bus and 18-bus test systems, a part of IEEE-14 and IEEE-30 bus systems, respectively.
Keywords: protection coordination; dual setting DOCRs; DS-DOCRs; mixed-integer nonlinear programming; MINLP; coordination time interval; time dial setting; plug setting.
DOI: 10.1504/IJPEC.2023.133619
International Journal of Power and Energy Conversion, 2023 Vol.14 No.1, pp.1 - 23
Received: 12 Nov 2022
Accepted: 26 Apr 2023
Published online: 25 Sep 2023 *