The normal operation of power system relies on accurate state estimation that faithfully reflects the physical aspects of the electrical power grids. However, recent research shows that carefully synthesized false-data injection attacks can bypass the security system and introduce arbitrary errors to state estimates. In this paper, we use graphical methods to study defending mechanisms against false-data injection attacks on power system state estimation. By securing carefully selected meter measurements, no false data injection attack can be launched to compromise any set of state variables. We characterize the optimal protection problem, which protects the state variables with minimum number of measurements, as a variant Steiner tree problem in a graph. Based on the graphical characterization, we propose both exact and reducedcomplexity approximation algorithms. In particular, we show that the proposed tree-pruning based approximation algorithm significantly reduces computational complexity, while yielding negligible performance degradation compared with the optimal algorithms. The advantageous performance of the proposed defending mechanisms is verified in IEEE standard power system testcases. Index Terms-False-data injection attack, graph algorithms, power system state estimation, smart grid security.
Bi and Zhang REF exploited the graphical defending algorithms against false-data injection attacks through protecting the state variables with the minimum number of measurements.
Graphical Methods for Defense Against False-Data Injection Attacks on Power System State Estimation
IEEE Transactions on Smart Grid
IEEE Transactions on Smart Grid
Computer Science