With the rapid development of electric vehicles (EVs), the wireless power transfer (WPT) technology of EV is becoming more and more mature. The safety of human electromagnetic exposure caused by the WPT system of EV has become the focus of research. Considering the practical application of EV WPT system, this paper studies the electromagnetic exposure of human body based on the uncertainty quantification theory. A sparse polynomial chaos expansion method is used to establish the surrogate model of the mean value of some human organs’ SAR, and the probability distribution function of SAR is calculated. The Sobol is used to quantify the impact of relevant variables on SAR. The final calculation results show that when the person is on the side of the EV, the offset between the magnetic coupling coils of the WPT and the lateral displacement of the human body on the side of the EV have a greater impact; When a person is at the rear of the EV, the vertical displacement of the magnetic coupling coils of the WPT has a greater impact on the longitudinal displacement of the human body at the rear of the vehicle. Combined with the above analysis, this paper can provide reasonable suggestions for the safety protection of electromagnetic exposure of human body in the WPT of EVs.

Electric vehicle (EV) is the core part of future automobile technology, and safe and reliable wireless power transfer (WPT) technology is the key link to improve the intelligent driving technology of EV. In this paper, the uncertainty quantification method is proposed to guide the optimization design of WPT structure, so as to improve the efficiency of WPT. First this paper establishes a surrogate model of WPT efficiency based on the adaptive sparse polynomial chaos expansion, and the uncertainty of EVs WPT transmission efficiency is quantified, the computational efficiency is improved by about 8.4 times. Then the surrogate model is combined with the global sensitivity analysis method to quantify the impact of different variables in WPT on efficiency and screen out the variables with greater impact. Finally, this paper uses the improved marine predators algorithm to optimize the selected WPT system structure parameters. Considering the uncertainty, the average efficiency of the optimized WPT system is increased from 73.43% to 94.64%. Compared with other optimization methods, it proves that the method in this paper can optimize WPT more efficiently, and significantly improve the transmission efficiency.

The Gaussian pulse generator is the core component of the pulse ground penetrating radar (GPR) system, which requires high amplitude, narrow pulse width, and low ringing levels. Marx circuits are widely used to generate Gaussian pulses. However, due to the complex pulse-forming process, the high-amplitude pulses generated by conventional Marx circuits suffer from oscillation and severe ringing. In this article, a refined model of the Marx circuit based on lossy transmission line theory is proposed, which effectively reduces the oscillation and ringing level of the generated Gaussian pulses. Furthermore, a monocycle pulse-shaping network is proposed based on the short-circuit stub. The unipolar Gaussian pulse is converted into a Gaussian monocycle pulse for antenna radiation. Waveform experiment results show that the peak-to-peak value of the output pulse is 428 V, the pulse width is about 0.8 ns, and the ringing level is low at about 9%. The profile imaging result of the sand tank detection experiment further shows that the generated high-quality Gaussian monocycle pulse can provide good detection performance of underground buried targets for the pulse GPR system.

For humans exposed to electromagnetic fields, metal medical implants pose more safety issues. The objective of this article is to analyze the safety issues of human electromagnetic exposure containing implants in the electric vehicle wireless power transfer (EV- WPT). This article establishes an adult male human model with a coronary artery stent and hip joint implant and is exposed to the leakage magnetic field of an EV -WPT system. The EV-WPT system has a transmission power of 30kW and a working frequency of 85kHz. Fully considering the uncertainty of human exposure to the electromagnetic environment of the EV-WPT system, such as the distance between the human body and the EV-WPT system, the distance between the EV-WPT system coils, and the parameters of the compensation circuit, this article uses Bayesian Neural Networks to evaluate human electromagnetic safety. Bayesian neural networks can obtain accurate results with fewer training sets and have higher computational efficiency. The results showed that the probability of electromagnetic exposure levels significantly exceeding the standard limit in the human body with hip joint implants was almost 100%, while the probability of exceeding the standard limit in the human heart with coronary artery stents did not exceed 31.5%. Patients with medical implants may need to limit power when using the EV-WPT system.

The aim of this paper is to analyze in depth the coupling between leakage electromagnetic fields (EMFs) generated by an electric vehicle wireless power transfer (EV-WPT) device under misaligned operating conditions and metallic coronary stents, which could be potentially hazardous to human electromagnetic safety. In this paper, we established that a standing human with a coronary stent implant and a sitting human with a coronary stent implant are exposed to the leaked EMFs of an EV-WPT device with a transmission power of 11 kW and 22 kW and a transmission frequency of 85 kHz, and we quantified the induced E-field strength of the human body by considering the x- and z-axis misalignment ranges of the WPT device as [−75 mm, 75 mm]. The results showed that the enhancement of the induced E-field in the human tissues near the sharp edges of the implant is significant. Meanwhile, the larger the WPT device misalignment generated, the higher the transmission power, and the closer the human body is to the WPT device, the larger the induced E-field_max value of the human body is, which has the possibility of exceeding the ICNIRP safety limit, and there is a potential human body electromagnetic safety problem.

Aiming at the problem that the leakage magnetic field (LMF) generated by wireless power transfer (WPT), a surrounding active shielding coil structure, and its fast multiobjective optimization design method is proposed. First, considering the problem that active shielding can reduce the efficiency of WPT, a surrounding active shielding coil structure that is inversely connected in series to the WPT coil is proposed, and the inner shielding coil compensates for the efficiency. Then, taking the efficiency of the WPT and the maximum magnetic flux density of the measurement surface as the optimization objectives, combining the data-driven polynomial chaos metamodel method and the optimization method based on the non-dominated sorting genetic algorithm, a fast multiobjective optimization design of the surrounding active shielding coil structure is achieved. Finally, an experiment was conducted using a 300 W WPT. At fixed observation point, the surrounding active shielding coil structure proposed in this article reduced the LMF by 86.97%, and the induced electric field strength of the human body exposed to the LMF was reduced by 65.40%, while the efficiency of the WPT was only reduced by 0.28%, proving the surrounding active shielding coil and its efficient design method are effective.