Wireless Power Transfer With HTS Transmitting and Relaying Coils

Using a high-temperature superconducting (HTS) coil as the transmitting coil is an optional way to increase the efficiency and the distance of a wireless power transfer (WPT) system. In practical cases, receiving coils might be not only one, or not convenient to get a low-temperature environment, or not in the same sizes with the transmitting coil. Thus, we constructed a WPT system from one HTS coil to two copper coils, and one of the copper receiving coils had a different size from the HTS transmitting coil. In addition, we placed one HTS relaying coil between the transmitting coil and the receiving coils to increase the efficiency and the distance. Based on this system, we conducted several experiments and analyzed the results. We found that a denser coil could obtain more power in an HTS WPT system and that WPT from one HTS coil to two copper coils was more efficient than WPT from the same HTS coil to one of the two copper coils. We also demonstrated that an appropriate layout of the HTS relaying coil can increase the HTS WPT efficiency.