Protection coordination for networked microgrids using single and dual setting overcurrent relays

• Published in: IET generation, transmission & distribution Vol. 14; no. 14; pp. 2818 - 2828
• Main Authors: Alam, Mahamad Nabab, Gokaraju, Ramakrishna, Chakrabarti, Saikat
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 17.07.2020
• Subjects: 69‐bus radial distribution system; coordinated operation; DERs; distributed energy resources; distributed power generation; DOCRs coordination scheme; dual setting overcurrent relays; efficient protection coordination scheme; interior point method; low voltage fault ride; multiple MGs; multiple microgrids; network topology; networked MGs; networked microgrids; NMGs; numerical analysis; numerical directional overcurrent relays; optimisation; optimisation problem; overcurrent protection; point of common coupling; power distribution protection; power generation faults; power generation protection; power generation reliability; power supply reliability; power supply resiliency; protection coordination problem; relay protection; Research Article; single setting overcurrent relays; protection coordination problem; numerical directional overcurrent relays; power supply resiliency; multiple microgrids; distributed power generation; power distribution protection; coordinated operation; optimisation problem; DOCRs coordination scheme; optimisation; power generation protection; relay protection; overcurrent protection; numerical analysis; power generation faults; 69-bus radial distribution system; efficient protection coordination scheme; power generation reliability; distributed energy resources; interior point method; point of common coupling; network topology; multiple MGs; NMGs; low voltage fault ride; networked MGs; single setting overcurrent relays; dual setting overcurrent relays; DERs; networked microgrids; power supply reliability
• ISSN: 1751-8687; 1751-8695; 1751-8695
• DOI: 10.1049/iet-gtd.2019.0557

The operation of multiple microgrids (MGs) with distribution system enhances reliability and resiliency of the power supply significantly by enabling high penetration of locally available distributed energy resources (DERs). However, there are several issues in the proper operation of multiple MGs that need to be addressed. Providing proper protection coordination is one of the most important issues in the coordinated operation of networked MGs (NMGs). In this study, an efficient protection coordination scheme for NMGs is proposed by utilising the commonly used numerical directional overcurrent relays (DOCRs) with single and dual settings. Issues related to the operation of NMGs such as the change in network topology, connection status of the point of common coupling and low voltage fault ride through of DERs have been considered. The protection coordination problem has been formulated as an optimisation problem and solved using the interior point method. The proposed protection coordination scheme of NMGs has been tested on the 69-bus radial distribution system with the integration of three MGs, which is not reported in earlier literature. The suitability and effectiveness of the proposed DOCRs coordination scheme have been demonstrated.