H∞ damping controller design in large power systems. Discussion. Author's reply

The design of an H∞ controller for a thyristor controlled series compensator to enhance the damping of an inter-area oscillation in a large power system is presented. The paper describes a comprehensive and systematic way of applying the H∞ control design algorithm in power systems. Two methods to obtain a satisfactory reduced order system model, which is crucial to the success of the design, are described.