State estimation and frequency stabilization of multi-area power systems via fault-alarm approach

This work is mainly focused on designing hybrid memory state feedback load frequency control law for a class of multi-area power systems against transmission delays, parameter uncertainties, actuator faults, and load disturbances via fault-alarm approach. More specifically, the load disturbances are prompted by the incorporation of abundance amount of renewable energy resources, namely, photo voltaic and wind power. Additionally, the power system takes the effect of actuator faults into account, which is unavoidable and exists at any instant of time. Thus, to stabilize the addressed system, the fault-alarm approach is exploited to develop the hybrid control law. Particularly, the state dynamics are well estimated by the aid of residual observer to detect the faulty condition of actuators. Also, by following the algorithm of fault detection, the spontaneous alert from the alarm is accomplished. Further, in consideration of appropriate Lyapunov-Krasovskii functional, the stability conditions having linear matrix inequality form are derived and which affirms the asymptotic stability of the power systems. Precisely, the controller gain matrices are obtained by solving the developed sufficient conditions. Eventually, the simulation results of two-area interconnected power systems are presented to examine the applicability and advantage of the proposed theoretical result.