Power system stability due to low synchronous reactance: Synchronous reactance is a third to a fifth lower
than that of conventional one. This makes steady state
and dynamic power stability improved. The sub-transient reactance of SCG is as same as that of conventional one, therefore transient short circuit current is as
same as that of conventional one.
Transient stability may be considered not to be improved since sub-transient reactance as same as that of
conventional one. However, some experimental studies
point out that SCG contributes improved transient
stability. The reason of it is considered that phase angle
of SCG is smaller than that of conventional one before
the transient states