A Risk Assessment Model for Distribution Systems Considering Optimal Defense Resource Allocation

Owing to the advancements in industry information technology, the traditional distribution network has evolved into a cyber-physical distribution system (CPDS), thereby introducing new challenges in quantifying the vulnerability of the system to cyber attacks. In addressing this issue, this paper proposes a novel risk assessment model with the example of cyber attacks on SCADA systems. To begin with, a risk propagation model is employed to construct a node network diagram for the SCADA system, facilitating the analysis of attack pathways and probabilities. Subsequently, physical metrics on the power side of the distribution network are established to quantify the physical consequences. Furthermore, defense costs against cyber attacks are computed, forming the basis for the development of a multi-objective optimization model for defense resources tailored to measurement devices, in conjunction with the proposed risk assessment model. Case studies and results demonstrate the performance of the proposed risk assessment model and defense resource optimization approach by contrast with existing ones.