Security Assessment of Cascading Failures in Cyber-Physical Power Systems With Wind Power Penetration

This paper presents a security assessment method for cascading failures of cyber-physical power system (CPPS) with high penetration of wind power. First of all, a mathematical model considering the cyber-physical coupling and cyber attack risks of power systems is established, and a stochastic model for wind power is developed based on Markov chain Monte Carlo (MCMC) method. On this basis, a cascading failure model of CPPS with wind power penetration is presented. To improve the accuracy of cascading failure simulation, a phase-estimated based linear power flow (PELPF) method is proposed, which not only maintains computational accuracy fairly close to that of Newton Raphson method but also significantly enhances computational efficiency and avoids convergence issues. Moreover, a restoration control model is built based on PELPF against cyber attacks in cascading failures. Finally, two security assessment indices based on power flow entropy are introduced, which can quantitatively evaluate the short-term and potential cascading failures propagation risks. Simulation studies are conducted on the IEEE 118-bus system under the conditions of cyber attacks and different wind power penetration rates to demonstrate the effectiveness of the proposed method.