Time-domain modeling of wireless power transfer in motion using inductively coupled flat spiral coils

WCU Author/Contributor (non-WCU co-authors, if there are any, appear on document)
Joshua Nathan Turnbull (Creator)
Institution
Western Carolina University (WCU )
Web Site: http://library.wcu.edu/
Advisor
Bora Karayaka

Abstract: In current commercial technologies, wireless power transfer (WPT) occurs when the item charging and the charger are not in motion. Products such as wireless chargers for cell phones, cars, and some internet of things (IoT) devices have stationary wireless chargers. A limiting factor of these chargers is in a single transfer coil system, the coils need to be aligned perfectly, and the device must be physically touching the charger. If it is not, minimal or no power is transferred, and the device is not charged. This set-up allows manufacturers to simplify design and modeling as a steady-state system. In this thesis, the receiving coil is in motion over the embedded transfer coil. The industrial standard to discern how the system would react uses finite element analysis (FEM), which is very resource-intensive and time-consuming. The point of this thesis is to model and approximate the potential of a WPT system to help discern the viability of designs, therein reducing the number of resources and time necessary to find an optimum solution. A Series-Series Compensated Wireless Power Transfer circuit was solved using Thevenin Equivalent Circuits and converted into a state-space equation. Using MATLAB® and Simulink, the circuit was modeled and compared to another study to validate the results. Variables such as frequency, load resistance, vertical and horizontal offset were then changed to see how the output voltage waveform and power transfer changed. Due to the receiving coil’s motion, a steady-state is not reached, and the system has transient states. The effects on the waveforms, thoughts about optimization, and possible future studies are discussed.

Additional Information

Publication
Thesis
Language: English
Date: 2020
Keywords
Motion, Power, Resonant, Time-Domain, Transfer, Wireless
Subjects
Electric coils
Time-domain analysis
Wireless power transmission

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