Research On Multi-direction Vibration Energy Harvesting System Based On Piezoelectric Materials

Most wireless sensor neworks use batteries to provide electricity power supply, which have the disadvantages of not only polluting the enviroment but also being inconvenience to replace the battery.A new method using environment energy to power the wireless sensor nework draws more and more attention. This paper focuses on the problems about the energy convertion structure for multiple direction vibration energy harvesting.The disadvantages of existing vibration energy harvesting structure have poor electrical energy conversion efficiency and short life .This paper develops a fold-type composite piezoelectric energy converting structure, and focuses on designing and researching the piezoelectric transducers which are composed of fold-type composite piezoelectric elements, A theoretical model of this fold-type structure is deduced and then simulated and analyzed using ANSYS . The simulation results of the ANSYS can be used to verify the theoretical model. By analyzing the disadvantages of the designed fold-type structural's characteristics, an improved structure is put forward. After structure optimiziation employing ISIGHT integrated optimization software, the structure is designed by CAD and then fabricated. Finally, verification experiments are carried out, which lies in three parts: experiment without load, experiment of amplitude-frequency and that with load. Afterwards, the natural frequency, the amplitude-frequency characteristics curve and the load characteristic curve of the structure are induced.The research shows that fold-type piezoelectric transducer structure can improve energy harvesting efficiency,further more, the service life of the structure can be prolonged by strengthening some part of the structure.