Abstract:
The wide application of communication equipment appears to increase the risk of cross-domain attacks on distribution networks' cyber-physical systems (CPSs). Against this background, the resilience enhancement strategy for CPS of distribution networks considering coordinated cyber-physical attacks is proposed. First, to analyze the fault propagation mechanism of CPSs under cyber-physical interactions, a virtual fault propagation network is built to identify the distribution network's fault and non-fault areas. Also, a virtual information flow network is proposed to represent the communication network and identify the working state of cyber nodes. This proposal uses a cyber-physical coupling constraint to describe the fault propagation process between the distribution and communication networks. Then, a robust optimization model under a tri-level framework of defense-attack-defense is established, in which the first-level defender develops the cooperative schemes for the remote-controlled switch deployment in distribution networks and the hardening of communication networks. The attacker seeks the most serious coordinated attack mode in the second level. Based upon the estimation of fault propagation impacts, the defender in the third level utilizes the remote-controlled switch action to reconfigure the distribution network into multiple microgrids and thus restore the power supply. The nested column constraint generation algorithm is used to solve the above model. Finally, the effectiveness of the proposed model and method is verified through case studies.