Advances and Challenges in Wireless Power Transfer for Modern Applications

Abstract

Based on seven specified documents, this paper systematically summarizes the core classification, applications, performance, and safety of Wireless Power Transfer (WPT) technology. WPT is categorized into near-field (non-radiative) and far-field (radiative) technologies according to energy transfer mechanisms. Near-field technologies, including inductive coupling and magnetic resonance coupling, are suitable for short-distance and high-efficiency scenarios, with inductive coupling efficiency reaching 80% to 90%. In contrast, far-field technologies, such as microwave and laser transmission, are mainly used for long-distance scenarios, though microwave-based transmission typically exhibits efficiency below 10%. In typical applications, the Qi-standard system for consumer electronics achieves an efficiency of around 85%, the static charging system for electric vehicles reaches approximately 89%, and the Wireless Capsule Endoscopy system can transmit 310 mW of power. These systems generally comply with the safety guidelines set by the International Commission on Non-Ionizing Radiation Protection. Currently, WPT faces challenges such as the trade-off between efficiency and transmission distance, as well as a lack of unified international standards. Future development should focus on advancing medium- and long-distance transmission technologies and promoting integration across diverse application scenarios.