New discovery for GaN HEMT applications, when matching the coil coupling coefficient with the parallel RLC resonance quality factor, the voltage gain from the power receiver to the transmitter increases with distance, the experiment uses a class E amplifier with GaN switch frequency controlling the copper coil current, which can transmit 50W at a distance of 50 cm with an efficiency of more than 65. The low parasitic capacitancehigh frequency of the GaN HEMT enable the transmitter coil to induce a higher voltage in the same magnetic flux.

In this study, the relationship between the resonance quality factorthe coupling coefficient was completed,a Sterling Cooler cooling device was designeddeveloped to cool the coil to 100K to obtain a lower coil resistanceimprove the received power of wireless charging, at a frequency of 6.7813.56 MHz, the GaN HEMT transistors which significantly improve power conversion efficiencymaintain higher operating frequencies will allows us to receive 10kW-level power at a distance of 50 cm in the future.

In this study, the relationship between the resonance quality factorthe coupling coefficient was derived,a Sterling Cooler cooling device was designeddeveloped to cool the coil to 100K, using GaN HEMT transistors to provide 10kW of power for electric vehicle charging. Another important point is that the WPT system powers flying drones, which are required to be compactlightweight. Maintaining resonance conditions consistent with loadenvironmental fluctuations is the key to wireless charging.