  The urgent need for the decarbonization of power girds has accelerated the
integration of renewable energy. Concurrently the increasing distributed energy
resources (DER) and advanced metering infrastructures (AMI) have transformed
the power grids into a more sophisticated cyber-physical system with numerous
communication devices. While these transitions provide economic and
environmental value, they also impose increased risk of cyber attacks and
operational challenges. This paper investigates the vulnerability of the power
grids with high renewable penetration against an intraday false data injection
(FDI) attack on DER dispatch signals and proposes a kernel support vector
regression (SVR) based detection model as a countermeasure. The intraday FDI
attack scenario and the detection model are demonstrated in a numerical
experiment using the HCE 187-bus test system.
