Design, fabrication and performance evaluation for the elastic elements coupled multi-frequency piezoelectric harvester

• Main Authors: CHUN-CHUN LAI, 賴俊俊
• Other Authors: 傅尹坤
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/w44x3m

碩士 === 國立中央大學 === 機械工程學系在職專班 === 103 === In this study, three models of elastic elements coupled multi-frequency piezoelectric harvester have been designed and developed as the application of vibration-based energy harvester. Through electrical tuning of the characteristic frequency and impedance matching, the output power of the three models of the harvester has been evaluated. The Type A model, a new piezoelectric cantilever generator using elastic spiral springs as a supporting mechanism, was fabricated for vibration-based energy harvester application to replace the basic of single-degree-of-freedom (DOF) cantilever generator system supported by a rigid metal bar. Under a base acceleration magnitude of approximately 1.5g, the strongest output power 10.7W was obtained at an optimum load resistance of 9.1kΩ. Under a base acceleration magnitude of approximately 0.5g, the strongest output power 0.01mW was obtained at a optimum load resistance of 8.2kΩ. The Type B model, a new piezoelectric cantilever generator using elastic metal sheet, was fabricated with multiple flexible materials to provide elastic elements coupled multi-frequency piezoelectric harvester. Under a base acceleration magnitude of approximately 1.5g, the strongest output power 0.54W was obtained at an optimum load resistance of 68kΩ. Under a base acceleration magnitude of approximately 0.5g, the strongest output power 116.8mW was obtained at an optimum load resistance of 91kΩ. The Type C model, a new piezoelectric cantilever generator using 3D printing to produce a cylinder where the circle cantilever beam is mounted in, was fabricated with elastic spiral spring to provide multi-frequency piezoelectric harvester. Under a base acceleration magnitude of approximately 1.5g, the strongest output power 0.41mW was obtained at an optimum load resistance of 68kΩ. Under a base acceleration magnitude of approximately 0.5g, the strongest output power 1.40mW was obtained at an optimum load resistance of 100kΩ. The generator could be a 2-DOF vibrating body, which can offer a wide resonance frequency bandwidth. Therefore, it is considered that the elastic spring enhanced the performance and frequency flexibility of the piezoelectric cantilever generator for broadband energy harvesting.