RGA applications in the control of flexible AC transmission systems

FACTS damping control is superimposed on FACTS normal control functions and hence its effectiveness can be hampered by the interactions between FACTS normal control and damping control function. This paper proposes a modified method based on the relative gain array (RGA) theory to assess the interactions between FACTS normal control and damping control function. The application of the proposed RGA method for the effective design of FACTS damping controllers is demonstrated by an example of selection of UPFC control function on which a UPFC damping control is superimposed.