Effective wireless power transfer at low-frequency enabled by high-temperature superconducting coils

Abstract Wireless power transmission (WPT) based on magnetically coupled resonance technology, providing high power energy transmissions at longer distances, is promising for practical applications such as the charging of electric vehicles. The traditional WPT system needs to operate at high frequencies to keep efficient energy transmission, and as a result, it requires a high-frequency AC power supplement where pronounceable energy losses may arise from. In the present paper, a high-temperature superconducting (HTS) WPT system is proposed to enable efficient energy transfer at low operating frequencies. The maximum output power and transmission efficiency of HTS-Cu and Cu-Cu WPT systems were compared experimentally with operating frequencies from 33 kHz to 342 kHz. The results show that the usage of the HTS-Cu WPT system can significantly improve the maximum transmission efficiency as well as the output power, especially at low operating frequencies. This provides a method for high-power WPT applications in the low-frequency range.