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Motivated by the transition to renewable energies in the context of ongoing climate change, offshore wind energy is of rising importance for the energy provision on national and international level. This trend, though, puts pressure on the safety and security community to provide appropriate analyses and solutions in regard to safety and security threats. Based on this motivation, this work investigates the internal disturbances in Offshore Wind Farms (OWF) provoked by cyber-attacks and severe electrical faults that might lead to high impact events. Therefore, the influences of these disturbances are quantified using a simulation model that represents electrical and mechanical aspects as well as the protection and control system. Furthermore, the dependence of the system response on to the disturbance characteristics is determined and the critical values of the disturbance characteristics leading to the OWF service interruption or even physical damage are identified. The results indicate in quantitative manner processes in the electrical and mechanical systems during parameter manipulations due to cyber-attacks and severe electrical faults. This, together with the quantitative signatures of the disturbances, enable future improvements of the security and stability of OWF systems. • Quantitative impact study of manipulations due to cyber-attacks on Offshore Wind Farms (OWFs). • Quantitative impact study of severe electrical faults on service provision of OWFs. • Application of Disturbance Impact Index for vulnerability analysis of OWFs. [ABSTRACT FROM AUTHOR]

The degradation of SRAM bit-cells designed in a 65 nm bulk CMOS technology in a Sun-Synchronous Low Earth Orbit (LEO) ionizing radiation environment is analyzed. We propose an inflight SEU rate estimation approach based on a modeled heavy ion cross section as opposed to the standard experimental characterization. Effects of irradiation with estimated LET spectrum in SRAM bit cell, i.e. the location of sensitive regions, its tendency to cause upset, magnitude and duration of transient current as well as voltage pulses were determined. It was found with SEU map that 65 nm SRAM bit-cell can flip even if high LET particle strikes in close proximity of bit-cell outside the SRAM bit-cell area. The SEU sensitive parameters required to predict SEU rate of on-board target device, i.e., 65 nm SRAM were calculated with typical aluminum spot shielding using fully physical mechanism simulation. In order to characterize the robustness of scaled CMOS devices, state of the art simulation tools such as Visual TCAD/Genius, GSEAT/Visual Particle, runSEU, were utilized whereas LEO radiation environment assessment, upset rate prediction was accomplished with the help of OMERE-TRAD software. [ABSTRACT FROM AUTHOR]

Space radiation environment at Low Earth Orbits (LEO) with perigee at 300 km, apogee at 600 km altitude having different orbital inclinations was modeled in the form of electrons and protons trapped in Van Allen Earth Radiation Belts (ERBs), heavy ions and protons in Galactic Cosmic Rays (GCRs), and Energetic Solar Particles (ESP) Events during solar maximum period. The co-relation between various shielding thicknesses and particles transport flux was analyzed for this specific orbit. We observed that there is an optimum shield thickness above which the attenuation of the transmitted flux of incident particles is negligible. To estimate the orbit average differential and integral fluxes to be encountered by onboard devices an appropriate radiation environment models were chosen in OMERE-TRAD toolkit and the impact of various shielding thickness for different orbital inclinations on integral Linear-Energy-Transfer (LET) spectra were determined. [ABSTRACT FROM AUTHOR]