Evaluation of Critical Node Groups in Cyber-Physical Power Systems Based on Pinning Control Theory

Blackouts have severely damaged cyber-physical power systems over the years, resulting in malfunctions that have rapidly spread within the electrical network. Selecting a set of critical nodes for human control can avoid similar situations. We propose a critical node evaluation method based on pinning control theory that uses a minimum nonzero eigenvalue of a modified Laplacian matrix as the evaluation index. Computational complexity can be markedly reduced using matrix analysis theory to sort screening conditions. Multiple nodes are controlled to form critical node groups in the directed weighted cyber-physical power system. We can thus more accurately find an optimal set of controlled nodes compared with other critical node evaluation strategies. Through theoretical and simulated verifications, we conclude that the addition of two nodes, which are used as active and standby dispatching centers of the communication network, is more effective and can result in a cyber-physical power system with better connectivity.