Recharging Portable Devices by Photovoltaic Modules Using Inductive Power Transfer

Abstract

Portable devices are part of people’s daily lives, since they provide the capabilities that make life easier. However, they consume much energy that requires continuous charging. Integrating renewable energy sources, especially photovoltaic (PV) modules into wireless charging, has been widely adopted in order to increase availability, flexibility, safety, and robustness. In this paper, a new variable frequency control technique for inductive power transfer (IPT) is proposed in order to overcome the switching frequency limitation and increase the transfer efficiency without increasing the switching frequency. At first, charging power (PV power) is stored in a battery. Then, it is transferred based on inductive coupling when needed. The hardware of the proposed wireless charging system has been carried out for two different configurations. The first one is the single switch using a variable frequency control algorithm, which has achieved 40% efficiency. The other one uses half-wave inverter applying no resonance for two types of core: Nano-crystalline and ferrite. For that configuration, the maximum achieved efficiency has been 80% at zero air gap and 36.91% at the 5 mm air gap by the Nano-crystalline core.