A novel approach to inter-area oscillation damping by unified power flow controllers utilizing ultracapacitors

This paper discusses a novel approach for damping inter-area oscillations in a bulk power network using multiple unified power flow controllers (UPFC) utilizing ultracapacitors, also known more generally as electrochemical capacitors (EC). In this paper, a new control is introduced to mitigate inter-area oscillations by directly controlling the UPFCs´ sending and receiving bus voltages which better utilizes the stored energy in the ECs. The results of this controller are compared with and without ECs. The proposed control provides better inter-area oscillation mitigation when applied to multiple UPFCs in the 118 bus IEEE test system.