Wireless capsule endoscopy (WCE) is noninvasive, painless, and riskless on detection for gastrointestinal disease. It attracts increasing attention. Wireless power transfer (WPT) technology is utilized to supply power for WCE. Receiving coil (RC) of WPT is capsulated into WCE. Its position and direction change all through gastrointestinal tract. Transmitting coil (TC) is worn by the patient. So the mutual inductance varies all the time. It should be studied to ensure sufficient receiving power. However, existing analytical methods do not reach satisfactory accuracy. They can only solve simple cases with positional misalignment. Numerical simulation models are time-consuming. Furthermore, an entirely new simulation must be repeated when any change in alignment occurs. Thus, based on geometry and misalignment of RC and TC, a model for mutual inductance is proposed. Compared with analytical methods, it is applicable to not only circular and rectangular RC, but also the elliptic, with directional misalignment. It costs below 0.1% of computational time of the simulation for the same accuracy. Moreover, any change in misalignment is easily handled by a simple change of parameter in the model. It reaches a tradeoff between computational accuracy and time. Receiving power is evaluated rapidly and accurately with proposed model.

中文翻译：

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胶囊内窥镜无线电力传输互感建模。


无线胶囊内窥镜（WCE）在检测胃肠道疾病方面无创、无痛、无风险。它吸引了越来越多的关注。利用无线电力传输（WPT）技术为WCE供电。 WPT的接收线圈（RC）封装在WCE中。它的位置和方向在整个胃肠道中发生变化。发射线圈（TC）由患者佩戴。因此互感始终在变化。应研究确保足够的接收功率。然而，现有的分析方法并没有达到令人满意的精度。他们只能解决位置错位的简单情况。数值模拟模型非常耗时。此外，当对齐发生任何变化时，必须重复全新的模拟。因此，基于 RC 和 TC 的几何形状和失准，提出了互感模型。与解析方法相比，它不仅适用于圆形和矩形RC，而且适用于具有方向不对中的椭圆形。对于相同的精度，其模拟计算时间的成本低于 0.1%。此外，任何不对中的变化都可以通过简单地改变模型中的参数来轻松处理。它达到了计算精度和时间之间的权衡。利用所提出的模型可以快速、准确地评估接收功率。