Extending the horizontal transmission range of an inductive wireless power transfer system using passive elliptical resonators

Abstract

This paper investigates the development of a passive elliptical planar coil for extending the horizontal transmission distance in an inductive transmitter-receiver wireless-power transfer system (WPT). The passive base coil partially overlaps the transmitter coil and extends the horizontal wireless link between the transmitter and receiver. The base coil models investigated are divided into three categories based on their length. Moreover, for each length category, the optimum number of turns is determined. All proposed models are analysed through the electromagnetic simulation (EMF) software Ansys-Maxwell and Simplorer as well as validated experimentally. For the entire analysis, the maximum efficiency principle is followed in this system. Therefore, impedance matching networks are used across all three terminals in order to tune the system to the operating frequency of 200 kHz to achieve maximum efficiency. The maximum achievable efficiency is determined for each coil prototype (in both simulation and experiment) and the results are compared. The extent to which the EMF software is a valuable tool in developing a planar passive base for an inductive WPT system is discussed. Overall, the proposed concept behind the passive base coil is proved to be successful in extending the horizontal distance between the transmitter and receiver.

A Comparative Review on Acoustic and Inductive Power Transfer

“…To solve this constraint, researchers studied the use of passive resonators to improve the transmission range of inductive wireless power transfer devices. This study employed passive elliptical resonators to improve the horizontal transmission range of an inductive wireless power transfer system [113]. The resonators were intended to resonate at the same frequency as the transmitter coil and were positioned between the transmitter and reception coils.…”

Analytical modelling with experimental validation of electromagnetic Halbach arrays in wireless power transfer systems

“…However, the study lacks a detailed explanation of the coil parameters and associated losses. Recently, a system configuration employing passive elliptical resonators was proposed to extend the horizontal transmission range [18]. This configuration significantly extends the distance compared to the conventional two‐coil system.…”