Resilience Enhancement for Power System State Estimation Against FDIAs with Moving Target Defense

False data injection attack (FDIA) by tampering with the sensor measurements is a big threat to the system’s observability. Power system state estimation (PSSE) is a critical observing function challenged by FDIAs in terms of its resiliency. Therefore, in this paper, we analyze the effectiveness of moving target defense (MTD) in enhancing the resiliency of PSSE against FDIAs. To begin with, the resiliency factor of PSSE against FDIAs is quantified using the relative estimation error against the injected measurement error. Then, the MTD is strategically designed to improve the resiliency factor by changing the line parameter and measurement case, for which the analytical results are provided. Furthermore, the infrastructure and operation costs caused by MTD are optimized to construct a cost-effective MTD. Finally, extensive simulations are conducted to validate the effectiveness of MTD in enhancing PSSE’s resiliency against FDIAs, which show that the MTD can improve the system’s resiliency factor by 10–20% and the generation cost can be reduced by about 10 USD/MWh after MTD.