Modeling and risk assessment of cyber physical distribution system based on cyber attack

With the continuous development of information and communication technology and its wide application in distribution network, distribution network has evolved into an cyber physical distribution network system(CPDS). The interaction between cyber and physical system means that power system faces greater potential risks. However, existing risk assessment methods do not take into account the coupling relationship between system network topology and equipment, and most of them only focus on physical system risk assessment. Therefore, this paper proposes a CPDS risk assessment method based on network attack. A method for calculating the prior probability of information nodes based on cumulative density function, FAHP and TOPSIS is proposed. Secondly, a physical node posterior probability calculation method based on SIS infectious disease model is proposed. Then, the optimal AC power flow model is established in the active distribution network, and the minimum load loss value is calculated. Finally, the risk value of network attack is calculated by prior probability, posterior probability and minimum loss of load. Through the simulation experiment of the improved IEEE33 system, the results show that the proposed method accurately evaluates the risk of network attack in CPDS.