High-fidelity modeling and topology optimization of propulsion and energy systems for distributed ducted fan eVTOL

Distributed ducted fan eVTOL propulsion and energy systems face drastic load power variations, difficulties in accurate working state evaluation, and substantial energy loss as well as heavy weight caused by complex power transmission cabling. This paper proposes a high-precision propulsion system state evaluation and energy system topology optimization method suitable for complex flight profiles. A propulsion system model including ducted fan, closed-loop Electronic Speed Controller (ESC) and motor is constructed, and the initial parameters of the model are obtained by identifying a small number of experimental data points. The energy system model suitable for high-voltage battery is established based on the Dual Polarization (DP) equivalent circuit. A dedicated power transmission system model is established to realize the dynamic information interaction of each sub-model. The state evaluation of the propulsion and energy systems under the complex flight profile is carried out for a scaled eVTOL prototype. Based on this, the optimality verification of the energy system topology scheme is completed. The results show voltage prediction errors below 1.96% for the energy system and current/power errors below 5% for the propulsion system. This evaluation method accurately reflects component state changes. Compared to traditional low-voltage platforms, the optimized topology achieves an 80.3% reduction in transmission system weight, 86.1% in cable power loss, and a 15.35% increase in post-mission battery State of Charge (SOC), verifying the method's accuracy and effectiveness.