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This paper presents the design and measurement results of wireless power transfer through soil over a range of soil moisture levels for future low-cost, wireless, battery-less, and in-situ soil health monitoring technologies. A pair of packaged 6 cm-diameter coils can wirelessly transfer 0.56 mW from an external RF power source of 37 mW through a soil depth of 15 cm over a typical moisture level ranging from low 30% to 40%. An optimal frequency of 1.4 MHz and 1 MHz was chosen for an efficient operation in loamy soil and sandy soil, respectively. The demonstrated power transfer is sufficient to energize underground soil health monitoring devices. In addition, a pair of packaged 12 cm-diameter coils, taking the loss contributed by the surrounding soil into design consideration, can achieve a 130 µW power delivery with an efficiency of approximately 8% over a 30 cm air gap. It is expected that a similar performance can be achieved through a 30 cm soil depth.
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Improving the Effective Range of a Through the Soil Long Range Wireless Power Transfer System Using a Marx Inverter Topology
With the growing research into Through the Soil wireless power transfer systems, power supply design research is necessary for determining a suitable topology capable of supplying high current density. A modified Marx inverter is chosen to complete this task due to the extremely high voltages produced. The presented analysis shows that TTS system performance metrics greatly improve with increased current density and high operating frequency. Finally, the inverter is used to operate a Through the Soil wireless power transfer system and its performance is assessed.
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- Award ID(s):
- 2226612
- PAR ID:
- 10629855
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-4913-9
- Page Range / eLocation ID:
- 257 to 260
- Format(s):
- Medium: X
- Location:
- Kyoto, Japan
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/WPTCE59894.2024.10557390
