Inductive charging technology of asphalt pavement: A state-of-the-art review

The increasing adoption of new energy vehicles has promoted the alleviation of petroleum fuel consumption and environmental problems. The charging and endurance capability problems of these vehicles are main constraints for their further development. The intelligent e-Road pavements can provide wireless charging, presenting a potential solution to the above deficiencies. This paper systematically introduced the composition and working principle of wireless charging technology to advance its development and application. Moreover, the main influencing factors of electric energy transmission efficiency on e-Road concerning pavement materials were analysed. The findings showed that the electric energy passed through pavement layers when applying the existing wireless charging technologies that typically use air as the medium. As a result, the transmission efficiency fluctuated owing to various influencing factors, including pavement materials, layers and moisture. This phenomenon is attributed to the performance parameters of wireless charging coils and the power loss caused by the electromagnetic induction characteristics of dielectric pavement materials. Potential solutions for improving the power transmission efficiency of wireless charging pavements were proposed, considering the circuit composition, asphalt concrete gradation type, and pavement structural composition. The methods and models used in previous studies were summarised to evaluate the dielectric loss of asphalt mixtures, and the wireless energy transmission efficiency, application scope, and optimisation methods were put forward. The impact of a commonly used wireless charging coil layout on the structure and service life of wireless charging pavements was analysed, and improvement measures were suggested.