Delayed-Input Power System Stabilizer using Supplementary Remote Signals

The design of a local H∞-based power system stabilizer controller, using wide area or global signals as additional measuring information considering time delay is presented in this paper. The wide area signals are taken from suitable remote network locations where the oscillations are well observable. A long time delay introduced by remote signal transmission and processing in wide area measurement system (WAMS), may be harmful to system stability and may degrade system robustness. Three methods for dealing with the effects of time delay are presented in this paper. To provide robust behavior, H∞ control theory together with an algebraic Riccati equation approach has been applied to design the proposed controller. The simulation results show that the designed controller contributes significantly to the damping of inter-area oscillations and the enhancement of small-signal stability in the presence of uncertainty in time delay under a wide range of system operating conditions.