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A Magnetically Coupled Electromagnetic Energy Harvester with Low Operating Frequency for Human Body Kinetic Energy
Xiang Li1, Jinpeng Meng1, Chongqiu Yang1
1School of Mechanical Engineering, Shandong University of Technology, Zibo 255049, China.
Micromachines
|November 27, 2021
Summary
This study introduces a novel magnetically coupled electromagnetic energy harvester (MCEEH) for human kinetic energy. The MCEEH efficiently harvests low-frequency energy, achieving significant power output for wearable devices.
Area of Science:
- Energy Harvesting
- Biomedical Engineering
- Materials Science
Background:
- Harvesting kinetic energy from the human body is crucial for powering wearable electronics.
- Existing methods often struggle with low-frequency motion and efficiency.
Purpose of the Study:
- To propose and experimentally validate a magnetically coupled electromagnetic energy harvester (MCEEH) for human kinetic energy.
- To enhance energy harvesting efficiency at low frequencies using a magnetic-spring structure.
Main Methods:
- Design of an MCEEH featuring spring-connected magnets and a free-moving magnet with repulsive interaction.
- Utilizing a magnetic-spring structure to mitigate hardening effects.
- Experimental investigation under harmonic and hand-shaking excitations.
Main Results:
- Resonance frequency achieved at 8.8 Hz with 0.5 g harmonic excitation.
- Maximum output powers of 5.2 mW, 2.8 mW, and 2.5 mW from three coils.
- Hand-shaking excitation yielded a peak voltage of 0.6 V and instantaneous power of 26 mW.
Conclusions:
- The proposed MCEEH effectively harvests human kinetic energy, particularly at low frequencies.
- The magnetic-spring design enhances efficiency and broadens the operational frequency range.
- Demonstrated potential for powering devices using natural human motion.
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