Research on Three-Coils Magnetic Coupling Resonant Wireless Power Transmission with Power Amplifier

The power of a three-coils magnetic coupling resonant Wireless Power Transmission (WPT) system driven by the signal generator is generally too small to be used directly. Adding a power amplifier before the transmitting coil of the three-coils magnetic coupling resonant WPT system is a promising solution to enhance the received power on the load, namely, the load power. The theoretical analysis of the three-coils magnetic coupling resonant WPT system is carried out, while the functional expressions of the load power and transmission efficiency are deduced. The position of the relay coil with maximum load power or transmission efficiency is analyzed for three different situations. The power amplifier parameters are designed by using the Advanced Design System (ADS) radio frequency simulation platform and then the prototype of the three-coils magnetic coupling resonant WPT system with a power amplifier is built and verified. The final results show that the load power can significantly increase from mill watt level to watt level by adding a power amplifier.