Study of Wireless Power Transfer and its Application in Harvesting of Solar Power with MPPT

Abstract

Nowadays wireless power transfer becomes one of the leading fields of research due to the rapid demand for portable, hermetically sealed devices and to get rid of fatigue and failure of the connectors. Also, the reliability of the system is increased due to the absence of wires. Wireless power transfer (WPT) system consists of two blocks at transmitter side i.e. highfrequency resonance inverter which converts DC power into high-frequency AC power that passes through inductive resonator which transfers power to the receiver side. Similarly, three blocks are present at the receiver side, i.e. inductive resonator for receiving the power, highfrequency rectifier for converting incoming high-frequency AC power to DC power and a power processing unit such as DC-DC converter to process the raw power according to the need of end devices at receiver side ( whether to charge a battery or power up any devices). Mainly two methods are widely used for transfer the power wirelessly, 1) Inductive coupling, where inductive resonance can be achieved by connecting external resonating capacitor with resonating inductor and 2) Magnetic resonance induction, where the resonance relies on the interplay between distributed inductance and distributed capacitance of resonant coil. The second mode is very much useful as it gives strong coupling in midrange transfer, but it uses high frequency (in the range of MHz) which is hard to implement. In this work, we experimentally studied methods and various issues, effects, and phenomena involved in WPT. We realize the inductive coupling methods at 232 KHz. Frequency splitting phenomena for over coupled system and power transfer to multiple receiver systems is also studied and analyzed. Finally, we show the application of WPT with a photovoltaic module for energy harvesting wirelessly. An MPPT based boost converter is built and connected to the PV module and the inverter at the transmitter side. This architecture of power transfer may be useful for smart home applications, charging wireless sensor network or any low power wireless devices.