자기공명 무선전력전송 효율 증대를 위한 초전도 코일 설계

Abstract

Recently, We has witnessed a soaring growth of IT such an advanced IT technology in has led to technical advancement where communication could be free from lines with wireless networks, such as mobile communication and Wi-Fi. As a result, electronic equipment, such as smart phones, smart TVs, or tablet PCs has advanced rapidly, and in education the e-book format, which was substituted for books and document files. Various effects are occuring in the fields of business including stock transactions. However, compared to the advancement of wireless communication and electronic devices, the inconvenience of the power system that delivers electrical power to these devices is increasing. Portable batteries need frequent recharging and changes, and power cables cause problems in terms of installation and mobility. To solve this issue, many have been interested in wireless power transmission(WPT) systems. continual researches on wireless power transmission systems have been made in various products such as magnetic induction wireless recharging systems or electric toothbrush systems. But magnetic induction wireless power transmission systems could only cover a short distance and require improvement to expand its scope of applications. To solve this problem, prof. Marin Soljacic team at MIT proposed a magnetic resonance method in 2007. The wireless power transmission system based on the magnetic resonance succeeded in turning on a 60W light bulb at a 2m distance, with 40% efficiency. Particularly, the magnetic resonance method offered a new paradigm of wireless power transmission technology by solving the biggest issue of the existing magnetic induction method and microwave method—distance, efficiency, and impact on the human body. However, the technology is still in its early stage, requiring further research on distance and efficiency. In this paper, we designed a superconductor coil to increase the efficiency of the magnetic resonance wireless power transmission system. The existing normal conductor coil might allow optimization through the size of the coil and winding method, but it was limited in efficiency improvement. However the superconductor coil has zero resistance at the critical temperature, allowing the increase of the Q-factor. Furthermore, the size of the current density could be increased by 100 times compared to that of the existing normal conductor coil, resulting in the maximum resonance characteristics with impedance matching. As a result, it has been shown that the implementation of the superconductor coil could improve the efficiency of the magnetic resonance wireless power transmission system more than the existing normal conductor coil.