Load Altering Attacks Detection, Reconstruction and Mitigation for Cyber-Security in Smart Grids with Battery Energy Storage Systems

In this paper, a novel scheme inspired by the Super-Twisting Sliding Mode Algorithm (STA) is proposed to detect, reconstruct and mitigate resonance load altering cyber attacks in smart grids. In the existing literature, it has been shown that these attacks are difficult to be detected by the control centre, as they are often characterised by relatively small power oscillations. Nonetheless, they can degrade the energy balance of the smart grid by making the frequency oscillating outside the tolerable limits. These attacks can further bring disruptive consequences, such as widespread blackouts and the disconnection of an area from the grid. In this study, it is shown that Battery Energy Storage Systems (BESSs) controlled by an observer-based STA can effectively mitigate the impact of these attacks on a smart grid. Specifically, an STA observer is created to detect and reconstruct in real-time load altering cyber attacks in a decentralised fashion. The estimation of the attack is then utilised as a set-point for a decentralised STA-based controller to dynamically regulate the output power of the BESS. The simulation results, which account for three possible scenarios, demonstrate the effectiveness of the proposed scheme.