Wireless Power Transfer System whose Input / Output Ratio is Determined Only by Self-Inductance

Wireless power transfer (WPT) technology is a power transmission system that does not necessitate an electrical contact. This study focuses on a simple design for WPT products through an analysis of a series/series-parallel (S/SP) WPT circuit scheme that exhibits the same input/output (I/O) characteristics as ideal transformers. S/SP is a circuit topology characterized by capacitors connected in series to a primary coil and in series-parallel to a secondary coil. Moreover, even with the inductor-capacitor-capacitor/series (LCC/S) scheme, determining a specific value for the compensation coil results in ideal transformer characteristics. To validate the theoretical results of the study, an experiment and a simulation are conducted, where solenoid type coils of the same shape and external dimension for the primary and secondary sides are applied for the S/SP and LCC/S WPT systems. Specifically, the experimental and simulated findings confirm that the winding number ratio of the coils and the I/O voltage ratio of the WPT system are in agreement.