Design And Research Of Piezoelectric-electromagnetic Hybrid Energy Harvester Applied To Human Body Motion Energy Collection

Collecting energy generated by human movement is a new research direction in the field of micro-energy collection,which provides a new idea and method for low-power device and continuous power supply of portable electronic devices and has broad application field and research value.Traditional energy harvester that collect energy generated by human movement have complex structure,small output voltage and low power density.Generally,they can only collect vibration energy in a single direction with low energy utilization rate.In order to overcome the existing problems of energy harvester that collect vibration energy generated by human movement,this paper designs a piezoelectric and electromagnetic hybrid energy harvester by combining the piezoelectric and electromagnetic energy conversion modes,which can collect vibration energy in two orthogonal directions at the same time.It has the advantages of simple structure,compact,easy to realize,and good power generation performance for low-frequency vibration energy generated by human movement.In this paper,the research on the piezoelectric and electromagnetic hybrid energy harvester mainly does the following work:The theoretical model of the designed piezoelectric and electromagnetic hybrid energy harvester is established for theoretical simulation,and the generation characteristics of the energy harvester under acceleration excitation in two orthogonal directions are analyzed.The fast Fourier transform(FFT)is used to verify the effect of frequency rising.The prototype of hybrid energy harvester was processed and a vibration experiment platform was set up to verify the theoretical simulation results.The comparison results show that the theoretical modeling and simulation analysis are correct.In order to verify the performance of the designed piezoelectric and electromagnetic hybrid energy harvester in collecting vibration energy generated by human activities,the treadmill-experiment platform and the hand-experiment platform were built respectively.In the treadmill-experiment,the hybrid energy harvester was fixed at the ankle,the power generation performance of the energy harvester was analyzed at different walking speeds,and the output waveform of each part of the energy harvester was processed with fast Fourier transform to verify the frequency-up effect of the hybrid energy harvester.Through the hand experiment,charging the energy storage capacitor and lighting the LED small lamp,the experiment shows that the output power of the piezoelectric and electromagnetic hybrid energy harvester can reach 16 m W under the hand excitation,which verifies the possibility that the hybrid energy harvester can power the portable electronic equipment through the energy of human activities.