State-Space Model of an Electro-Mechanical-Acoustic Contactless Energy Transfer System Based on Multiphysics Networks

Contactless energy transfer systems are mainly divided into acoustic, inductive, capacitive, and optical, in which main applications are related to biomedical, wireless chargers, and sensors in metal enclosures. When solids are used as transfer media, ultrasound transducers based on piezoelectricity can be used for through-wall power transfer, which can be named as an electro-mechanical-acoustic contactless energy transfer system. This work presents a state-space model derived from a multiphysics network that includes all the multiphysical power conversion without separating the stages and including the real physical elements, like as the piezoelectric parameters and the geometry of the transfer media. The model is compared to the experimental response of the system and evaluated for different scenarios regarding transducers types and solid transfer media. An error analysis has shown that the maximum quadratic error between theoretical and experimental responses is 3.7%.