An Active Detection Scheme for Cyber Attacks on Grid-tied PV Systems

This paper introduces an active defense mechanism against cyber attacks in grid-tied Photovoltaic (PV) systems connected at the distribution level. The core of such a defense mechanism dynamic watermarking approach is to detect malicious manipulation of voltage/current sensor measurements feeding inverter control. The defense mechanism is described in detail and several attack possibilities, based on manipulating the current measurements, are described. Three attack models are used to test the validity of the proposed approach on a single-phase, 5 kW, grid-tied inverter, connected at the distribution level.