Alternative Configuration of Open-Bifilar Coil for Self-Resonant Wireless Power Transfer System

The use of self-resonant coils for wireless power transfer is a promising field since it avoids the use of a real capacitor. It is known that the classical inductor model leads to a parallel-circuit resonance with maximum impedance at resonant frequency. However, series compensation in transmitter and receiver circuits (series-series) is the simplest configuration of a wireless power transfer system. In this study an alternative configuration of an open-bifilar coil is presented. In this way, it is possible to obtain a series self-resonant frequency with minimum impedance at resonance, which allows a series-series compensation, capacitorless wireless power transfer (WPT) system.