A novel approach for power system oscillation damping incorporating SSSC facts device

Abstract

Due to the deregulation of the electrical market difficulty in acquiring rights of way to build new transmission lines and steady increase in power demand maintaining power system stability becomes a challenging problem In large interconnected power systems power system damping is often reduced leading to lightly damped electromechanical modes of oscillations Implementation of new equipment consisting high power electronics based technologies such as Flexible Alternating Current Transmission Systems FACTS and proper controller design become essential for improvement of operation and control of power systems FACTS technologies offer competitive solutions to today s power systems in terms of increased power flow transfer capability enhancing continuous control over the voltage profile improving system damping minimizing losses etc The power system may be thought of as a large interconnected nonlinear system with many lightly damped electromechanical modes of oscillation If the damping of these modes becomes too small or even positive it can impose severe constraints on the system s operation It is thus important to be able to determine the nature of those modes find stability limits and in many cases use controls to prevent instability The poorly damped low frequency electromechanical oscillations occur due to inadequate damping torque in some generators causing both local mode oscillations 1 Hz to 2 Hz and inter area oscillations 0 1 Hz to 1 Hz newline newline newline