SVD-UPFC BASED DESIGNATION OF VERSATILE CONTROLLERS TO DAMP LOW FREQUENCY OSCILLATIONS

Unified power flow controller (UPFC) is the most reliable device in the FACTS concept. It has the ability to adjust all three control parameters effective in power flow and voltage stability. In this paper, a linearized model of a power system installed with a UPFC has been presented. UPFC has four control loops that, by adding an extra signal to one of them, increases dynamic stability and load angle oscillations are damped. In this paper, after open loop eigenvalue (electro mechanical mode) calculations, state-space equations has been used to design damping controllers and it has been considered to influence active and reactive power flow durations as the input of damping controllers, in addition to the common speed duration of synchronous generators as input damper signals. SVD controllability measurements determine the most effective control input to apply to the system. Dynamic stability has been improved via Lead-Lag and LQR controllers’ designation.