Electromagnetic Side-Channel Noise Intrusion on Solid-State Transformer

This paper delves into the intricacies of electromagnetic side-channel noise intrusion (EM-SNI) and its impact on the voltage sensors of a solid-state transformer (SST). As described in this work, the EM-SNI attack can be easily deployed using a small antenna, and its effects spread without any electrical contact with the power-electronics hardware circuitry or measurement signal feedback. The cyber-physical attack is performed by injecting noise at very high frequencies (MHz range), and due to the aliasing effects of the analog-to-digital converter sampling, corrupt the feedback signal as sub- and super-60 Hz harmonic frequencies. Hence, this paper details how the EM-SNI mechanism works and analytically discusses the aliasing effects on noise frequency injections that could potentially harm the SST system. Subsequently, a method to detect and mitigate the impact of electromagnetic side-channel noise injection (EM-SNI) on the SST system is proposed to counteract its effects. The method involves a cross-correlation-based intrusion detection and voltage feedback observation on the instantaneous power-transfer relationship for mitigation. Experimental results confirm the effectiveness of the proposed methodology and are presented throughout the paper.