SSC compensation capability of unbalanced voltage sags

In this paper, the capacity of a static series compensator (SSC) to compensate for voltage sags is discussed, and a complete analysis of the effects of unbalanced sags on the SSC compensation capability is carried out. Expressions are obtained for the missing voltage during unbalanced voltage sags. These expressions are used to estimate how often a voltage sag occurs where the missing voltage exceeds the injection capability of the SSC. The method is applied to a typical Italian network configuration.