A long time delay due to the transmission and processing of remote signal may degrade
stability of power system. This paper discusses the design of H? -based local
decentralized delayed-input PSS (Power System Stabilizer) controllers for a separate
better damping of inter-area modes. The controllers use selected suitable remote
signals from whole system as supplementary inputs. The local and remote input signals,
used by the controller, are the ones in which the assigned single inter-area mode is
most observable. The controller is located at a generator which is most effective in
controlling the assigned mode. The controller, designed for a particular single interarea
mode, also works mainly in the natural frequency of the assigned mode. Pade
approximation approach is used to model time delay. The time delay model is then
merged into delay-free power system model to obtain the delayed-input power system
model. The controllers are then redesigned for the delayed-input system