Affiliation:
1. Institute of Energy, Environment and Climatic Change, Hellenic Mediterranean University, 714 10 Iraklio, Greece
2. School of Engineering, Power Systems and Energy Engineering, Hellenic Mediterranean University, 714 10 Heraklion, Greece
Abstract
This paper proposes a sophisticated, fault-tolerant, and centralized secondary controller that is designed for inverter-based, islanded microgrids. The proposed controller enhances system resilience to unexpected network partitions, which typically occur due to the tripping of protective devices under fault conditions. In typical radially configured MGs, a line fault can cause protective devices to isolate the faulted line, thereby splitting the MG into two electrically independent sub-microgrids (SMGs), while retaining the existing communication and control framework. In contrast to traditional centralized and distributed secondary controllers, which often fail to restore the frequency to the nominal value (50 Hz) in split SMGs, the proposed controller exhibits exceptional performance. Through simulation studies on 6-bus and 13-bus islanded MG setups, the controller has not only demonstrated its ability to swiftly restore the nominal frequency in both SMGs within a few seconds (specifically 5 s), but also to ensure fair power distribution among the distributed generators (DGs) supplying the SMGs. This rapid frequency stabilization underscores the controller’s effectiveness in maintaining stable frequency levels immediately following a fault. In contrast, the use of traditional centralized and consensus controllers typically results in a frequency deviation of about 3 Hz from the nominal value in one of the SMGs during the microgrid’s partition.
Funder
project “Enhancing resilience of Cretan power system using distributed energy resources (CResDER)”
Hellenic Foundation for Research and Innovation
Action “2nd Call for H.F.R.I. Research Projects to support Faculty Members and Researchers”
Reference25 articles.
1. Power-flow-based energy management of hierarchically controlled islanded AC microgrids;Chopra;Int. J. Electr. Power Energy Syst.,2022
2. Modelling the steady state of secondary control in islanded AC microgrids;Pompodakis;Int. J. Electr. Power Energy Syst.,2023
3. Performance evaluation of secondary control policies with respect to digital communications properties in inverter-based islanded microgrids;Marti;IEEE Trans. Smart Grid,2018
4. Secondary control of microgrids based on distributed cooperative control of multi-agent systems;Bidram;IET Gener. Transm. Distrib.,2013
5. Secondary frequency and voltage control of islanded microgrids via distributed averaging;Shafiee;IEEE Trans. Ind. Electron.,2015