Research And Design Of A Class E Power Amplifier For Magnetical Coupled Resonance Wireless Power Transfer

In recent years, wireless power transmission technology has been widely adressed by scientists and engineers in the worldwide. Magnetical coupled resonance wireless power transmission is an effective candidate to solve the problem of wireless charging for most of electronic devices due to its relatively farther power transmission distance. In this thesis, a high efficiency class E power amplifier for the magnetic coupledresonance wireless power transmission system is designed and applied to the audio system with magnetic coupled resonance wireless power transmission. The experimental results shows that the signal and energy cooperative transferring with improved efficiency is realized.Firstly, class E power amplifier circuit that is applied in magnetic coupled resonance wireless power transmissions is analysed based on the frequency power amplifier design theory. A class E power amplifier with parallel circuits is designed and simulated using Agilent ADS software.Secondly, a PCB layout of class E power amplifier is designed by a reasonable placement and routing. A class E power amplifier with center frequency of 10 MHz is fabricated by the discrete components. According to the measurements, an 25 dBm, input power can lead to a maximum power additional efficiency of 88.9%, output power of 45.2dBm and gain of 20.2dB. The experimental results show that the the design target is acheived.Finally, an audio system of magnetic coupled resonance wireless power transmission is designed and fabricated.The system includes voltage controlled oscillator circuit, driving circuit, class E power amplifier, receiving and transmitting resonant coils, rectifying and filtering circuit, and power supply module. The measurement results show that the maximum effective transmission distance of the system is 60 cm. A high quality horn sound is got when the transmission distance in the system is between 25 cm to 35 cm. At the same condition, the load can receive power of 14.9W with a 49.6% efficiency for all the system. The experiment provides an evident that the class E power amplifier can be used in magnetic coupled resonance wireless power transmission system with a high transmission efficiency.