Design and Analysis of Wireless Nanogrid for Non-Smartphones

ABSTRACT This research work designs a wireless power transfer system (WPT) for non smart phones as an alternative to existing wired power supply systems for these devices. Initially, the general concept of known WPT systems and methods are introduced and reviewed. It was noted that most existing WPT models do not consider external interferences in their design even though, it is well known that high frequency circuits may interfere with a WPT system. Additionally till date, existing WPT systems are designed for smart devices only. To fill in this gap, a basic magnetic induction WPT architecture was developed. It consisted of an input driver, inductively coupled transmitter and receiver and a load driver where the load is a non-smartphone. In each stage of the architecture, the efficiencies ηj−k of the power transfer process are calculated. The inductive coupling is represented by a magnetic circuit in which external interferences are modeled as series reluctances. The power flows and efficiency were obtained by Langrangian energy methods. The flexibility of the design was demonstrated by the low order of variation in the system efficiency over generalized coordinates of load rotation, displacement and impedance. Comparing the WPT system designed in this work with [9], a maximum parameter variation over rotation of 1% was obtained. Additionally, an effective range of 4.5m where [9] had a variation over rotation of 6% and a range of 1m. Finally, the research work recommended that a specific design incorporating a solar photovoltaic source is introduced to improve the stability and reliability of the wireless power supply system.