Design considerations for wireless charging in heavy-duty electric commercial vehicles

The increasing adoption of wireless charging systems for electric vehicles is largely driven by their ease of use and low maintenance requirements. However, when it comes to heavy-duty electric vehicles (HDEVs), the need for high power, large battery capacity, and long driving range requires a more comprehensive approach to system design and analysis. In this study, both AC and DC-based wireless charging systems were evaluated using the TEMSA LD SB E model, developed by TEMSA SKODA SABANCI ULAŞIM ARAÇLARI A.Ş., as a reference. Within the scope of the study, the energy transfer efficiencies of both systems were modeled in MATLAB/Simulink across a range of coupling coefficients (from k = 0.10 to 0.90) and resonant frequencies (80, 85, and 90 kHz). The AC-based system employed a high-frequency inverter with eight switching devices and a Series-Series (SS) resonant topology, while the DC-based system utilized a direct DC/DC converter structure. Simulation results revealed that system efficiency varied depending on the coupling coefficient and frequency, with the highest values observed in the DC system at 97.44% and in the AC system at 96.10%. At low coupling coefficients, a noticeable drop in energy transfer efficiency was observed in both systems. This decline can be directly attributed to the weak magnetic interaction between coils when k is low, which limits the amount of energy transferred and thus significantly affects overall system performance. Finally, sensitivity analysis was performed using linear modeling and the finite difference method to identify the parameters that most influence system efficiency. In addition, transient analysis was carried out with the fourth-order Runge-Kutta method to evaluate how quickly each system reaches steady state. The findings confirm that wireless charging is a practical solution for heavy-duty electric vehicles and provide a solid foundation for future engineering improvements and design studies.