A 5 Watts Magnetic Resonance Wireless Power Transfer with Enhanced Transmission Distance Capability

Wireless power transfer (WPT) technology and application are becoming popular in recent years. It is a re-emerging technology to allow simple, easy to use and convenient techniques to propagate electricity from power source to an electrical load over a distance with no electrical cord. This paper presents one method to increase the transmission distance of WPT. This study is essential to reach the maximum power delivery due to power efficiency (one of WPT limitations). A WPT system based on the magnetic resonance method was developed. It works at the resonance frequency of 140kHz in the maximum transmission range of 30cm and achieving maximum power delivery of 5W at 7cm transmission range. The experiment result shows that this method can achieve a power transfer efficiency of around 55%. The use of high-quality electronic components for the resonator circuit has to be considered in the design process to address the problem of resonance frequency tuning between transmitter and receiver coils.