Robust control of unified power flow controller (UPFC)

Abstract

This paper investigates control methods for the unified power flow controller in order to improve thestability of a power system hence providing security under increased power flow conditions. Theseinclude a direct PI controller with decoupling (PI-D), MIMO internal model control, multivariableGPC, multivariable GPC with decoupling algorithm (GPC-D) and adaptive fuzzy logic controls. Theperformances of the controllers are evaluated under different operating conditions of the powersystem. The results demonstrate that IMC, GPC, multivariable GPC-D and FLC are very effective inimproving the transient power system stability and very robust against variable transmission lineparameters.