Experiments on Coexistence of Microwave WPT and Energy Harvesting with a Matrix Switching Circuit and Solar Power Cells

DC power supplying is an important problem for the practical use of IoT with massive sensors. There are two techniques for such supplying. One is the wireless power transfer (WPT) technique and the other is energy harvesting. This paper focuses on the combination of WPT and energy harvesting. WPT can transmit higher power to the receiving equipment than that energy harvesters can collect. Reversely, energy harvesting is a more environmentally friendly power supply method than WPT. WPT is an active charging method, whereas energy harvesting is a passive charging method. Herein, the combination of WPT and energy harvesting is a suitable power supply method for IoT. This research is focusing on the i-v characteristics of rectifiers and solar power cells. We experimented the characteristics of a rectifier with differential input power and solar power cells with room light. We also experimented the i-v characteristics of multi-connected rectifier and solar power cells. Our proposing matrix switching circuit is used for the multi connection. This matrix circuit enables any connections for the DC power sources. The experimental results shows both positive and negative effect on the DC power supplying.