Characteristic analysis of novel Double-Fork piezoelectric energy harvester

With maturity of micro-electro-mechanical system (MEMS) technology, varieties of electronic products have entered into the era of integration, miniaturization and low power consumption. It is noted that the traditional battery power supply method restricted the development of electronic products. Vibration energy harvesting is one of the most promising solutions. Because the vibration frequency in normal circumstance is about 1–100Hz, the lower resonant frequency of piezoelectric harvester is demanded. Based on the piezoelectric effect, the characteristics of a novel kind of Double-Fork piezoelectric energy harvester (DFPEH) was studied. A model of the DFPEH was built in the finite element analysis software ANSYS, and the corresponding static analysis, modal analysis, harmonic response analysis were made sequentially. Results show that the first three order resonance frequencies of the harvester are 21Hz, 47Hz and 91Hz separately, which are suitable for low-frequency vibration environment. The frequency gap between the first-order resonant frequency and the second-order resonant frequency is 26Hz. Besides, the 3dB bandwidth of the first-order resonant frequency is 8Hz under condition of acceleration value 9.9m/s2 and the damping factor 0.025, which is applied on the fixed end of the DFPEH. Consequently, the DFPEH has shown the distinguished broadband characteristic.