A Synchrophasor State Estimator Algorithm That Guarantees Immunity Against GPS Spoofing

Abstract

Power system state estimation using Phasor Measurement Units (PMUs) is a core functionality in the energy control centers executed with milliseconds granularity. Its results can be compromised by GPS spoofing of the PMUs. This paper proposes a novel synchrophasor state estimator algorithm that is immune to GPS spoofing. This guarantee holds so long as less than 50% installed PMUs are spoofed. The average runtime complexity of the proposed algorithm is the same as that of the linear synchrophasor state estimator, while its worst-case complexity is almost equal to that of a traditional nonlinear state estimator. Hence, it is very efficient. It is also highly sensitive i.e., it can detect sub-degree-level spoofing attacks. As a byproduct, it also identifies the spoofed PMUs and the quantum of spoofing without the overhead of any additional optimization or state estimation runs. Case studies and comparative evaluations on the IEEE-30 bus and the IEEE-118 bus system demonstrate the validity of the claims made.