Active safety protection of CPS considering the importance of information network nodes

The modern cyber-physical system (CPS) is a complex system in which the power network. The information network provides transmission, communication and control of information for the power network. However, it is also a high-value target for network attacks. The network attacks in the form of network shock virus can simulate accuracy attack instructions like normal operation which can initiate line tripping that cannot be completely eliminated by existing protection system of domestic power system. To avoid causing large-scale blackouts when the information network suffers malicious attacks, the importance index of power network nodes is proposed considering entropies degree. The important nodes of the information network are obtained according to the coupling relationship between the power network and the information network. Then, a power node protection method which sets up corresponding trap nodes in the information network is proposed. The simulation analysis of load loss based on the IEEE118-node system shows the proposed model significantly improves the protection against the attacks of malicious network.