Design of decentralized load frequency regulator for two-area power systems subject to bounded persistent disturbances

This paper presents the design of decentralized load frequency regulator for two-area power systems in which each area´s disturbance is bounded persistent change in load demand. In the formulation of the design problem, all of such disturbances that happen or are likely to happen in practice are treated explicitly as signals having uniform bounds on magnitude and slope. The design problem is solved by using two known principles: namely, the principle of matching and the method of inequalities. Once a design solution is found, one can ensure that the frequency deviations and the tie-line power deviation always remain within prescribed bounds in the presence of all possible disturbances. The numerical results show that the framework adopted here is suitable and effective, thereby giving a realistic formulation for the load frequency control problem with persistent disturbances.