电力信息物理融合系统结构脆弱性分析

为了识别电力信息物理融合系统(Cyber Physical Power System,CPPS)脆弱性并制定相应脆弱性防控策略,从结构的角度,建立电力网为IEEE118节点系统、双星型信息网和网型信息网2种具有不同子网络结构的CPPS相依网络模型.提出一种相依节点对重要度综合指标,该指标可以辨识对CPPS结构脆弱性产生重大影响的相依节点对,克服单层网络指标的局限性.基于相依网络连锁故障模型,分别采用随机攻击策略和蓄意攻击策略,分析2种CPPS的结构脆弱性,并研究关键节点保护策略对2种CPPS结构脆弱性的影响.仿真结果表明,随机攻击策略下,网型信息网CPPS的结构比双星型信息网CPPS更加脆弱.蓄意攻击策略下,优先攻击相依节点对对网络连通性的破坏程度更大.合理选取关键节点保护策略的保护节点可以改善系统的结构脆弱性.

Analysis on Structural Vulnerabilities of Cyber Physical Power Systems

To identify the vulnerabilities of Cyber Physical Power System (CPPS) and formulate the corresponding prevention and control strategy, the models of two kinds of CPPS interdependent networks with different subnetworks were presented, in which IEEE 118 bus system was chosen as Power Grid and cyber networks adopted two typical structures: double-star and mesh, respectively. An index of comprehensive importance on interdependent pairs of nodes was proposed, and it was used to identify the key pairs of interdependent nodes causing large influence on CPPS structural vulnerabilities, which overcomed the limitations of single-layer network indicators. Based on the model of cascading failures in interdependent network, CPPS structural vulnerabilities were analyzed by using two extreme attack strategy: randomly attack and deliberately attack. The effect on CPPS structural vulnerabilities of Key Node Protection Strategy was considered. Simulation results indicate that, compared with double-star cyber network CPPS, the structure of mesh cyber network CPPS is more vulnerable under randomly attack. Under deliberately attack strategy, prior attacking pairs of interdependent nodes can cause more damage to network connectivity. CPPS structural vulnerabilities can be improved with selecting proper nodes of Key Node Protection Strategy.