Optimal communication-free protection of meshed microgrids using non-standard overcurrent relay characteristics considering different operation modes and configurations based on N-1 contingency

Authorsشکیبا صادقی میرلطف اله,حامد هاشمی دزکی
JournalSustainable Cities and Society
Page number1
Volume number106
IFثبت نشده
Paper TypeFull Paper
Published At2024-03-24
Journal GradeScientific - research
Journal TypeElectronic
Journal CountryIran, Islamic Republic Of
Journal IndexSCOPUS ,JCR

Abstract

Smart grids (SGs), meshed active distribution networks (ADNs), and microgrids (MGs) frequently experience reconfigurations and changes in their operation modes (grid-connected and islanded), which leads to protection miscoordination and speed challenges. Several research works have studied the protection of MGs/SGs, considering different configurations. On the other hand, non-standard relay characteristics provide some flexibility in protection design. However, the literature review shows that less attention has been paid to the optimal protection of MGs/SGs, incorporating non-standard relay curves and consideration of N-1 contingency configurations and operation modes. This paper aims to respond to this research gap. Also, the slow tripping of backup relays, a common drawback of recent works, is concerned with a modified objective function (OF). The presented coordination optimization problem (COP) is formulated in a mixed-integer nonlinear programming-linear programming (MINLP-LP) form and solved using hybrid heuristic-linear programming algorithms: Genetic algorithm-particle swarm optimization-linear programming (GA-PSO-LP) and water cycle algorithm-moth flame optimization-linear programming (WCA-MFO-LP). The introduced research is applied to the distribution portion of the IEEE-14 test system. The analysis and discussions emphasize that the proposed protection scheme speed is improved by over 36 % compared to available ones. Also, there is no coordination violation under different system configurations.

tags: Directional overcurrent relays (DOCRs)Microgrids (MGs)Smart grids (SGs)N-1 contingencyCoordination optimization problem (COP)Standard and non-standard relay characteristics