Design of a wireless power transmission system for sensors in a household environment

Abstract

Application of computing and communication systems towards monitoring physical devices enables the Industrial Internet, a smart system of sensors integrated within physical objects. A major challenge associated with designing a practical system of sensors is designing an economically viable means to power them at such a large scale, which a wireless power transmission system could facilitate. This thesis addresses the challenge of selecting an appropriate strategy for power transmission and demonstrating its feasibility within a household environment. The first part of the thesis examines potentially feasible strategies for transmitting power to sensors in a household setting. Existing technologies are surveyed and evaluated against the functional requirements associated with this application. Resonant inductive coupling is selected based on its suitability towards the desired application for reasons of power level, safety, obtrusiveness, and efficiency. The second part of the thesis describes the processes of design, simulation, fabrication, and testing of a prototype resonant inductively coupled power transmission system. An accelerometer-based sensor module that communicates via radio frequency is powered by a resonant inductively coupled power transmission system, which consists of a large (1.07 m diameter) transmitter coil embedded within a table and a small (0.038 m diameter) receiver coil adhered to a water bottle. A suitable amount of power is supplied to the receiver module when it is placed within 95% of the primary coil diameter up to a height of 20 cm, and up to a vertical height of about 40 cm along the central axis of the primary coil.