非线性双端固支梯形梁压电俘能器结构设计与特性分析

A kind of nonlinear double-end fixed trapezoidal beam piezoelectric energy harvester (PEH) was designed to collect the vibration energy in the environment, piezoelectric energy harvester can transform vibration energy to electricity to supply for miniature electronic components. The vibration frequency of vibration sources was mostly below 100 Hz in natural environment, in order to reduce the resonant frequency, widen bandwidth and improve output performance of the piezoelectric energy harvester, the non-contact magnetic force was introduced. On the basis of theoretical analysis, Matlab/Simulink simulation model was established and experiment was carried out to compare the resonant frequency, bandwidth and output performance of linear and nonlinear double-end fixed trapezoidal beam piezoelectric energy harvester. Meanwhile, the response of output performance when three parameters (the space d between fixed magnet and mass block magnet, external load resistance R and the external excitation acceleration a) change was studied. The results of simulation and experiment showed that the introduction of non-contact magnetic force can reduce the resonant frequency of the piezoelectric energy harvester by 9 Hz, widen its bandwidth by 20% and increase its output power by 7.5%.