Microgrid overcurrent fault analysis

What is adaptive overcurrent protection of AC microgrids?

1. 2. In adaptive overcurrent protection of AC microgrids, settings of DOCRs are changed according to the system operating conditions. Mostly, settings of the relays are changed in this scheme whenever a transition occurs between the islanded and grid-connected modes.

Can a microgrid protect against a non-adaptive overcurrent?

In non-adaptive overcurrent protection of AC microgrids, optimum setting of DOCRs are obtained with the ability to coordinate properly in both islanded and grid-connected modes. In , protection coordination of microgrid with islanded and grid-connected modes of operation has been discussed.

What is fault current magnitude in a microgrid?

Fault current magnitude in a microgrid depends upon its mode of operation, namely, grid-connected mode or islanded mode. Depending on the type of fault in a given mode, separate protection schemes are generally employed.

Can dual-setting overcurrent relays be used in a microgrid test system?

Thus, the proposed protection scheme using dual-setting overcurrent relays also provides the common optimal relay settings for larger test system such as the 18-bus microgrid test system which can be used in both operating modes.

Is directional overcurrent protection a viable solution for a microgrid?

Although it seems that differential protection is the most viable approach in such a microgrid, other approaches such as current derivative, directional overcurrent, distance protections could be appropriate candidates if advanced signal processing or other methods will address their challenges.

How to detect faults in DC microgrids?

In , cable current derivatives are utilized to detect faults in DC microgrids. Alternatively, traveling wave (TW) protection schemes have been introduced to accommodate a faster tripping protection in electric power grids. These schemes rely on high-frequency measurements.