Resonant Beam Charging (RBC) is a promising Wireless Power Transfer (WPT) technology to realize long-range and high-power charging for electronic devices. However, the safety mechanism of the RBC system has not been investigated so far. In this paper, we propose an analytical model based on electromagnetic field analysis for evaluating the performance of the RBC system with external object invasion, such as the benchmark for the WPT safety, irradiance on the invading object. For the RBC system with 5 m transmission distance and 1 W output electric power, the safety numerical analysis of radiation illustrates that the maximum irradiance on the invading object is 0.81 W/cm2, which is approximately 1/101/10 compared with 8.22 W/cm2 for the comparable laser charging system. Particularly, the peak irradiance on the invading object of the RBC system satisfies the Maximum Permissible Exposure (MPE) requirement for human skin, which is 1 W/cm2 in the standard “Safety of Laser Products IEC 60825−160825-1”. Hence, the RBC system can realize skin-safe WPT with Watt-level power over meter-level distance.

中文翻译：

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使用谐振束进行远距离大功率无线电力传输的安全分析


谐振束充电（RBC）是一种很有前景的无线功率传输（WPT）技术，可实现电子设备的远距离、大功率充电。然而，迄今为止，RBC系统的安全机制尚未得到研究。在本文中，我们提出了一种基于电磁场分析的分析模型，用于评估RBC系统在外部物体入侵时的性能，例如WPT安全性的基准、入侵物体的辐照度。对于传输距离为5 m、输出电功率为1 W的RBC系统，辐射安全数值分析表明，入侵物体上的最大辐照度为0.81 W/cm2，约为8.22 W/cm2的1/101/10。 cm2 用于类似的激光充电系统。特别是，RBC系统入侵物体上的峰值辐照度满足“激光产品安全IEC 60825−160825-1”标准中对人体皮肤的最大允许暴露（MPE）要求，即1 W/cm2。因此，RBC系统可以实现米级距离、瓦级功率的皮肤安全WPT。