A Comparison of Analytical Models for Resonant Inductive Coupling Wireless Power Transfer

Recent research in wireless power transfer (WPT) using resonant inductive coupling has demonstrated very high efficiencies (above 40%) at large distances compared to the antenna dimensions, which has exponentially increased the number of potential applications of WPT. Since resonant inductive coupling is a very multidisciplinary field, different approaches have been proposed to predict the behaviour of these systems from physical theory of resonators, reflected load theory and the circuit point of view. However, the relation between these methods is still obscure. In this article, we compare the results of these models to find the efficiency of a Resonant Inductive Coupling WPT system under Steady-State sonditions and to analyze the relation between the optimal load values obtained from this perspectives and the ones obtained using impedance matching techniques.