Optimization Algorithms for Catching Data Manipulators in Power System Estimation Loops
For power system operators, it provides a method to secure estimation loops against attacks that could destabilize the system.
The paper develops algorithms to detect malicious data manipulators in distributed optimization loops for estimating oscillation modes in power systems, enabling quick identification of compromised estimators without model information.
In this paper we develop a set of algorithms that can detect the identities of malicious data-manipulators in distributed optimization loops for estimating oscillation modes in large power system models. The estimation is posed in terms of a consensus problem among multiple local estimators that jointly solve for the characteristic polynomial of the network model. If any of these local estimates are compromised by a malicious attacker, resulting in an incorrect value of the consensus variable, then the entire estimation loop can be destabilized. We present four iterative algorithms by which this instability can be quickly detected, and the identities of the compromised estimators can be revealed. The algorithms are solely based on the computed values of the estimates, and do not need any information about the model of the power system. Both large and covert attacks are considered. Results are illustrated using simulations of a IEEE 68-bus power system model.