Study on safe distance between human body and wireless charging system of electric vehicles with different power and frequencies

Abstract

In this paper, a wireless charging system and a human body model with various operating frequencies and output power are constructed to study the safe distance between the human body and the charging system when the electric vehicle is wirelessly charging. The models are simulated for electromagnetic fields and electromagnetic thermal effects. This paper mainly focuses on the induced electric field intensity of the human body and main organs during the static charging of electric vehicles under different operating conditions in a wireless charging system. The results are compared with the standards established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) to derive the minimum safe distance for electric vehicles charged wirelessly. The results show that when the system works at a frequency of 85 kHz with output power of 3.7 kW, 7.7 kW, 22 kW, 33 kW, 66 kW, and 150 kW, the minimum safe distance between the human body and the system is 0.5 m, 0.6 m, 0.7 m, 1.0 m, 1.2 m, and 1.7 m; when the system works at an output power of 66 kW with frequency of 85 kHz, 300 kHz, 500 kHz, and 700 kHz, the corresponding minimum safe distance is 1.2 m,0.9 m, 0.8 m, and 0.6 m. Moreover, the induced electric field intensity distribution of human organs at different power is also calculated, and the results show that the induced electric field intensity of the liver and kidney is higher than that of other organs. When the human body is at the minimum safe distance, the temperature changes caused by the electromagnetic heating effect of various organs are within the normal adjustment range of the human body, indicating the rationality of the minimum safe distance when the electric vehicle wireless charging system works under parameters of this paper. It provides a theoretical basis for the setting of the safe distance of the electric vehicle wireless charging system.