Implementing Admittance Relaying for Microgrid Protection

TL;DR

This paper investigates the use of admittance relaying as an effective protection method for inverter-interfaced microgrids, addressing challenges posed by low short-circuit currents in such systems.

Contribution

It demonstrates the feasibility of admittance relaying for microgrid protection through analytical and simulation comparisons, filling a gap in existing protection strategies.

Findings

Admittance relaying is suitable for inverter-interfaced microgrid protection.

Analytical and simulation results agree on the effectiveness of admittance relaying.

Four experiments confirm the reliability of the proposed protection method.

Abstract

The rapid increase of distributed energy resources has led to the widespread deployment of microgrids. These flexible and efficient local energy grids are able to operate in both grid-connected mode and islanded mode; they are interfaced to the main power system by a fast semiconductor switch and commonly make use of inverter-interfaced generation. This paper focuses on inverter interfaced microgrids, which present a challenge for protection as they do not provide the high short-circuit current necessary for conventional time-overcurrent protection. The application of admittance relaying for the protection of inverter-interfaced microgrids is investigated as a potential solution. The comparison of analytical and simulated results of performed four experiments prove the suitability of admittance relaying for microgrids protection.