Effect of multi-functional UPFC upon power system oscillation stability

This paper presents the analysis of the interaction between the damping and other control functions of a unified power flow controller (UPFC) installed in power systems. A case of negative interaction between the UPFC damping control and voltage control of the DC link capacitor is studied and then an algorithm for their co-ordinated design is suggested. An example is given in the paper to demonstrate the analytical results and the success of the co-ordinated design.