Safety assessment of electromagnetic fields of different transmitters and receivers for EVs static charging

This study aims to assess the safety aspect of future inductive charging stations by investigating the electromagnetic fields performance of various pad architectures. Following the recommendations of the standard {Society of Automotive Engineering (SAE J2954)}, which suggests two common pad kinds for the inductive power transfer (IPT) system (circular pad (CP) and double-D pad (DDP). The safety analysis is performed on the car side using these two types of pad architectures, with ground clearance compliant with Z3-class requirements and a power transfer of 11.1 kVA. In one scenario, a DD pad serves as the universal ground side pad (transmitter), while in the other scenario, a Circular pad is utilized. Safety assessments are performed using four models constructed based on 3D finite-element models (FEMs) and resonant networks. Circuit models are employed to establish the frequency of operation and resonant network components necessary to attain the rated transmitted power with maximum efficiency (η). Electric fields (E) and electromagnetic fields (EMFs) were calculated under ideal alignment conditions as well as in various cases of misalignment, including angular and lateral misalignments. The results demonstrate that the two distinct car side pads (CP and DDP) can function with the universal transmitter regardless of whether a CP or DDP is utilized, and that both types of car side pads (receivers) can achieve a high level of safety. Meanwhile, electric and electromagnetic fields stay within the bounds allowed by the 1998 and 2010 versions of the ICNIRP guidelines.