Recent years have seen numerous efforts to make wireless power transfer (WPT) feasible for application in diverse fields, from low-power domestic applications and medical applications to high-power industrial applications and electrical vehicles (EVs). As a result, it has been found that WPT by means of non-radiative magnetically-coupled resonant circuits is an optimum method for mid-range applications where the separation of source and receiver is in the range of 1-2m.This thesis investigates various aspects of the design of magnetically-coupled resonant circuits for non-radiative WPT. Firstly, a basic four-coil network for a mid-range (1-2m gap) WPT system with a single power source and single resistive load was developed and simulated. The system was then constructed and experimental results were obtained for comparison with theoretical expectations. Methodologies were developed for empirical measurement of flux-coupling coefficients (k) among the coupled resonator coils and measurement of resonator parameters (inductance, capacitance, and equivalent-series resistance). Secondly, a structure called a universal resonator is proposed to permit design of WPT networks of arbitrary complexity with multiple power sources (transmitters) and multiple loads (receivers). An Excel simulation tool has been developed to analyze designs involving up to eight resonators. Designs with five resonators (including one power source and two loads) and six resonators (with two power sources and two loads) with separation of 1m between transmitting and receiving resonators have been analyzed, constructed, and subjected to experimental validation. The measured outputs numerical were found to be in good agreement with the predicted models. Conclusions and suggestions for future work are provided.
Date of publication
Nagoorkar, Varun, "Midrange Magnetically-Coupled Resonant Circuit Wireless Power Transfer" (2014). Electrical Engineering Theses. Paper 23.