Minimization of Interrupted Power by Optimal Power Flow Control with Multiple UPFCs

Abstract

Our study aims at minimization of power not supplied (PNS) under the severe fault condition such as tripping of double circuits of transmission lines. In this paper, we propose a new static control method which can minimize PNS by coordinately controlling multiple unified power flow controllers (UPFCs), generators and loads. The proposed method is based on multiple optimal power flow (OPF) calculations, and determines not only control variables of UPFCs but also which and how much generators and loads should be shed after the fault. Digital simulations are carried out with the IEEE RTS-24 system. Three simulation cases, with and without UPFCs, and with uncontrollable UPFCs, are compared and the results shows that reduction of PNS can be accomplished by UPFCs with the proposed control method. Furthermore, it is made clear that the multiple OPFs, which consider the priority loads to be shed, are very effective on reduction of total PNS.