Design and measurement of low EMI and high efficiency handheld resonant magnetic field charger (HH-RMFC) for wireless power transfer electrical vehicle

Abstract

In recent years, hybrid and Plug-in electric vehicles are becoming an increasingly important part of the automotive market. Battery charging method is an also important part to manufacturers. Among the various charging methods, the inductive charging has advantages in terms of electrical safety and convenience. Induc-tive charger consists of the primary part (i.e., the Tx winding) and the secondary part (i.e., the Rx winding). The combination of primary part and secondary part magnetically transferred power. The AC currents flowing through the primary and secondary windings produce time-varying electromagnetic fields (EMF) in and around the inductive charging system. It has become more important to consider EMF effect, and not just the power transfer efficiency. Time-varying EMFs can cause interference in electrical and electronic devices. Moreover, long-term human exposure to time-varying EMFs can also be very harmful. The harmfulness to human health has been well documented and explained by the International Commission on Non-Ionizing Radiation and Pro-tection (ICNIRP), World Health Organization (WHO), the International Agency for Research on Cancer (IARC) and national expert groups. In this paper, 2kW-class inductive charger operating at high frequency of 20 kHz for electric vehicle is proposed and analyzed. The proposed Handheld Resonant Magnetic Field Charger (HH-RMFC) was designed considering low EMI and high efficiency.