Designing and analyzing multi-coil multi-layers for wireless power transmission in stent restenosis coronary artery

Wireless power transfer technology features shorter power transmission distances in biomedical applications. This is a result of the small size of the implanted coils, biocompatible material conductivity, and the large distances between the receiving and transmitting coils. There have been numerous attempts to improve the power transfer efficiency across longer distances. Multiple coils, including 2-, 3-, 4-, and multi-layered coils, were previously considered. This study proposes a novel approach to achieve higher power transmission efficiency by integrating a single coil on the receiving side and three asymmetric coils on the transmitter side. As such, it delivers power to the sensor implanted within the coronary artery that monitors the blood pressure while introducing a uniquely shaped stent. The efficiency of power transmitted to the stent in its dual implanted forms, helical and zigzag helical, was examined as well, with the wireless power transmission system thereby analyzed at the 27 MHz Industrial Scientific Medical band operating frequency. For the four-coil technique, the power transmission efficiency at a distance of 25 mm between the receiver and transmitter sides by using biological human tissue as a medium between the transmission coils and the receiver stent can reach 56.42%, whereas other approaches show lower efficiencies: the three-coil method’s efficiency is 32.88%, the double-layer parallel method’s efficiency is 27.75%, the two-coil method’s efficiency is 24.76%, the triple-layer parallel method’s efficiency is 17.31%, the double-layer series method’s efficiency is 0.501%, and the triple-layer series method’s transmission efficiency is 0.092%. In addition, the suggested approach is demonstrated to be more efficient than prior designs with regard to the size of the implanted coils, which represent stents.