Evaluation and selection of shielding methods for wireless charging of e-rickshaw

High leakage magnetic fields are inevitable for wireless charging (WC) of electric vehicles (EVs), due to their large air gap. This high leakage magnetic field may cause adverse effects on human beings in the vicinity. So the design of coil system of WC system to satisfy the safety limits as well as performance is quite important. The electromagnetic fields exposure to human beings should be less than the safety regulations set by International Commission on Non-Ionizing Radiation Protection. Moreover, EVs' chassis creates unwanted electrical load on the WC affecting the performance and can be improved through shielding of leakage magnetic fields as per the standards. The main focus of this paper is to first investigate the effectiveness of passive, active and resonant current loop shielding methods through finite element method approach considering asymmetrical circular spiral coils. Based on the outcomes, a passive shielding on the receiving side and inductive coil connected in series opposing configuration with transmitting coil have been proposed for the case of e-rickshaw. Accordingly, coil system is fabricated for the air gap of 12 cm and experimental evaluation is carried out.