The usage of open communication infrastructure for transmitting
the control signals in the Load Frequency Control (LFC) scheme of power system
introduces time delays. These time delays may degrade the dynamic performance
of the power system. This paper proposes a robust method to design a controller
for multi-area LFC schemes considering communication delays. In existing
literature, the controller values of LFC are designed using time domain
approach which is less accurate than the proposed method. In proposed method, the controller values are determined by moving the rightmosteigenvalues ofthe systemto the left half plane in a quasi-continuous way for apreset upper bound of time delay. Then the robustness oftheproposed controller is
assessed by estimating the maximumtolerable value of timedelay for maintaining system
stability. Simulation studies are carried out for multi-area LFC schemeequipped withthe proposedcontroller
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