Electromagnetic Environment Characteristics And Bioelectromagnetic Safety Assessment Of Electric Vehicle Wireless Charging Station

In recent years,the energy crisis has broken out widely around the world,and electric vehicles as one of the mitigation measures,their research and development and upgrading of various technologies have continued to make breakthroughs.Various technologies are widely used in the field of electric vehicles,and wireless power transfer(WPT)technology has broad application prospects due to its advantages such as flexible charging,safe operation,and maintenance-free interface.At present,WPT technology has developed relatively mature,which can provide charging services for small devices.However,the wide application of WPT technology still faces many challenges,among which the issue of electromagnetic safety has become a bottleneck restricting the further development of WPT.In order to obtain the quantitative understanding of the electromagnetic environment around the WPT system in practical application,this paper tests and simulates the electromagnetic environment of the WPT system.Firstly,a simulation model with a shield is established in COMSOL,which simulates the positive alignment,offset,deflection and air gap change of the coupling mechanism,and the results show that the non-ideal working state will lead to an increase in the electromagnetic field value in some areas.The WPT simulation experiment system was built in the laboratory,and the electromagnetic field values at typical measurement point positions were measured,and the test results and calculation results were compared with the simulation to verify the effectiveness of the modeling method.Secondly,the joint simulation model of wireless charging station of a single WPT system is established,and the electromagnetic safety of the two scenarios of standing outside the car and sitting inside the car is analyzed at the power levels of 7.7kW,11kW,22kW and 33kW using the height level analysis method of the human model,and the results show that the four power levels of the standing scene outside the car will make the induced current density of the human foot exceed the limit value of ICNIRP1998 of 170 mA/m2.Finally,the simulation model of two wireless charging stations of WPT systems arranged in parallel is established,and the model parameters are adjusted,and the effect degree of inverting operation and inverted operation of the two WPT systems on the electromagnetic safety of the standing scene outside the car under the four power levels is obtained,and the results show that the human body is safe in this scenario.In this paper,the electromagnetic environment distribution characteristics of wireless charging stations are analyzed,and the electromagnetic environment distribution of WPT system can be effectively predicted with the help of this modeling.