Design of a High-Voltage Bonding Network for a Hybrid Electric Aircraft

Abstract

High-voltage (HV) power networks for more- and hybrid-electric aircraft enable high-power distribution but introduce new electromagnetic compatibility (EMC) and lightning protection challenges. This paper proposes a dedicated High Voltage Bonding Network (HVBN), segregated from the airframe, to provide a controlled return path and contain transients. We summarize installation requirements and an architecture for HV equipment, and optimize HVBN geometry for low impedance and weight using finite-difference time-domain (FDTD) simulations and an inductance-mass Figure of Merit; three realizations are selected across strap/rod/cable implementations. The HVBN is validated against representative threats - indirect lightning (waveforms A/H), DC short-circuit at $\pm \mathbf{4 0 0 V}$, and serial arcing at 350 V - on a fuselage model with realistic equipment placement. Results show very low current transfer to the structure (below 1A in normal operation and 7A under failures), limited voltage leakage under DC fault (below 60 V) and arcing (below 0.05 V), and transient spectra confined to $\mathbf{4 M H z}-\mathbf{1 0 0 M H z}$ and largely contained within the HVBN. These findings support concise EMI/EMC grounding and lightning protection guidelines tailored to HV systems while remaining compatible with existing LV practices, and they inform future HV installation and qualification standards.