Novel resilient compensator design for FDI attack mitigation on AGC system

Abstract

ABSTRACT For proper functioning and stability of a power system, it is of utmost importance that the system frequency is kept within permitted operating limits using the Automatic Generation Control (AGC) else stability is compromised. This may lead to disruption of system operation and/or damage of the power grid equipment. The AGC system must be protected against false data injection (FDI) attacks as the information required by AGC is transmitted to the control centre by the means of communication links which are vulnerable against cyber-attacks. Hence, to overcome this issue a Generalized Extended State Observer (GESO) based resilient sliding mode compensator is developed in this paper. GESO is used for the purpose of detecting FDI attacks against the AGC system. In order to mitigate the effect of the FDI attack in the system, sliding mode compensator is utilised. It not only mitigates the effect of attacks but also allows the control centre to make its decision based on the uncompromised sensor signals instead of the compromised signals. The proposed method is subjected to a variety of FDI attacks and the simulation results confirm its competency to successfully detect, estimate and compensate for FDI attacks regardless of the effect of AGC nonlinearities.