Detection and Mitigation of Gps Spoofing Attacks on Smart Grids

Sensors such as phasor measurement units (PMUs) are widely used in the power systems. PMUs equipped with global positioning system (GPS) receivers measure nodal voltages and line currents in the network. In this dissertation, the effect of a particular type of cyber attack, namely, GPS spoofing on power system state estimation (SE) is analyzed. This attack occurs on installed PMUs and it manifests itself as a shift in phase angles of PMU measurements. A novel measurement model for static and dynamic network is developed. An alternating minimization (AM) algorithm is developed to perform joint state estimation and attack reconstruction. The standard IEEE transmission test networks are used to show the effectiveness of the aforementioned algorithm. Numerically, performance improvement is observed by using dynamical network model compared to its static counterpart. For static case, additional supervisory control and data acquisition (SCADA) measurements are used to analyze the effect on accuracy of SE. Furthermore, the effect of pseudo-measurements on GPS spoofed SE is analyzed. Modest improvement is observed in static SE under pseudo-measurements.