Low-Cost Embedded Circuit for Self-Tuning of Impedance Matching in Wireless Power Transfer Devices

Seeking to improve wireless power transfer efficiency, a low-cost embedded circuit for self-tuning of impedance matching is proposed and successfully demonstrated. Applying the Maximum Power Point Tracking (MPPT) algorithm, the equivalent capacitance value on a L-match circuit is automatically changed.

The theoretical, analytical and numerical simulations of the whole wireless power transfer system were also performed. Finally, the experimental circuit was implemented in order to demonstrate the efficiency of the system. In the experimental setups the power transfer efficiency increased: 4.84% for 20cm, 5.21% for 30cm, 25.90 for 40cm and 24.09 for 50cm, respectively.