Enhanced voltage relay for AC microgrid protection

Author(s)

Santos, G. P. ; Tsutsumi, A. ; Vieira, J. C. M.

• Document type: Journal article
• Source: Electric Power Systems Research; v. 220, p. 6-pg., 2023-03-16.

Abstract

Microgrids emerged as an efficient way to integrate distributed energy resources and local loads into power distribution systems, allowing the local system operation in grid-connected and islanded modes. However, the microgrids imply several challenges for the protection systems, such as the changes in fault current path and the decrease of the fault current amplitude during islanded operation. Therefore, conventional overcurrent protec-tion does not guarantee selectivity, coordination, reliability, and adequate trip time in AC microgrids. Under this perspective, voltage-based relays have been widely investigated as a potential protection for AC microgrids. Thus, this paper critically reviews voltage-based protection and proposes improvements to an existing technique, aiming to simplify the settings and guarantee reliability and selectivity among various voltage-based protection devices. The results showed that our modifications improved the selectivity and reliability of the voltage-based protection compared with the original technique and the traditional overcurrent protection devices for different topologies of an AC microgrid. (AU)

• FAPESP's process: 21/04872-9 - Evaluating technical impacts on the expansion of distributed generation for smart grids
• Grantee: Denis Vinicius Coury
• Support Opportunities: Regular Research Grants