Assessment of the Electromagnetic Radiation Exposure at EV Charging Facilities

As the number of electric vehicles (EV) increases, the number of EV chargers also increases. Charging infrastructure will be built into our close environment. Because of this, the assessment of the electromagnetic field exposure generated from the charger is an important issue. This paper valuates the electromagnetic field exposure of six EV chargers. To assess the level of exposure of EV chargers, the electromagnetic fields from six chargers were measured and analyzed. In addition, measured electromagnetic field exposure levels were evaluated against ICNIRP guidelines. Higher electromagnetic fields were measured with standard chargers than with fast chargers. For the fast charger in the charging state, the magnetic field increased with the charging current. Electromagnetic field exposures for all six chargers did not exceed standard limits. The results of the assessment of the electromagnetic field exposure of the six EV chargers will contribute to the establishment of standards for the evaluation of the electromagnetic field exposure of the EV chargers in the future

Characteristics analysis of resonance-based wireless power transfer using magnetic coupling and electric coupling

This study analyses the wireless power transfer of the resonance-based magnetic coupling method and resonance-based electric coupling method and provides information about the characteristics of each. To compare the characteristics of each method, the power transfer efficiency was analysed according to the transfer alignment and misalignment distance between the transceivers. More specifically, they were theoretically analysed through equivalent circuit models, and the results were verified through electromagnetic numerical analysis simulation and the fabrication and experimental results of a wireless power transfer coupler. Although both methods differ according to the coupling method, in terms of power transfer efficiency, it was found that they are determined by the same physical phenomena. Furthermore, in both methods, a null-power point occurred during misalignment between the transceivers. The misalignment distance within which the null-power point occurred is intrinsically determined by the structure of the resonant coupler

Resonant-Based Wireless Power Transfer System Using Electric Coupling for Transparent Wearable Devices and Null Power Points

This study provides information on the transfer efficiency of four-plate-structured copper plate and metal mesh sheet couplers, the cause of null-power point. The couplers are compared based on the equivalent circuit model analysis, experimental results of fabricated couplers, and simulation results of the High-Frequency Structure Simulator (HFSS) tool. It was confirmed that the metal mesh material exhibits the same performance as the existing copper plate and can be fully used as a coupler material for the electrical resonance wireless power transfer system. In addition, the null-power point phenomenon is only determined by the main coupling and cross coupling between the transmitter and receiver, which are most dominantly affected by the coupler structure