Page 160 - Hybrid-Renewable Energy Systems in Microgrids
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144 Hybrid-Renewable Energy Systems in Microgrids
Figure 7.18 Short-circuit current leaving Bus 3 under unbalanced faults in the middle
of line 3-4 with prefault condition (2) (A) Balanced current control, A-B fault. (B) Balanced
current control, A-g fault.
Figure 7.19 Short-circuit current leaving Bus 3 under unbalanced faults in the middle
of line 3-4 with prefault condition (3) (A) Balanced current control, A-B fault. (B) Balanced
current control, A-g fault.
which is similar to a traditional power system. However, this kind of logic does not apply
for a microgrid operating under islanded mode when there is no support from the utility
grid. In contrast, the short-circuit contribution from converters is restricted in each phase
considering their limited overload capabilities of semiconductors. This results in a much
lower short circuit current level in an islanded mode microgrid.
