The transition towards cleaner energy resources has led to the increased penetration of converter-interfaced distributed generators (DGs) and the extensive use of information & communication technologies (ICT) in power systems. Although recent efforts have been made to understand, model, and classify converter interactions, much remains unexplored. This complex dynamic structure of emerging smart grids, is a result of DGs' advanced controllers, communication links and the hardware itself. In that framework, the digitization of power systems introduces new vulnerable points that are susceptible to cyber threats. Building on the knowledge stemming from computer science, cyber attacks targeting power systems have been classified, with false data injection (FDI) attacks identified as one of the most common threats. In this paper, the impact of a microgrid's operational and design parameters on its cyber resiliency under FDI attacks on the secondary controller is showcased. In particular, in a modern islanded microgrid comprising grid forming inverters for increased flexibility, and distributed secondary control being implemented as part of its hierarchical control, the impact of the droop gain and the R/X ratio of the lines on the microgrid's inherent cyber-resilience against FDI attacks is demonstrated. In the analysis the current limitation is taken into consideration as studies often focus solely on the small signal stability properties of a system, overlooking the power constraints.
