宽频自调谐压电振子发电性能研究

Power generation performance analysis of broadband self-tuning piezoelectric vibrator

传统悬臂梁固定方式下压电振子频带较窄,存在环境适应性差、发电效率低的问题。为此,提出了一种通过改变固定位置实现宽频的自调谐压电振子。建立了调谐模型,对压电振子在不同固定位置的发电性能进行了仿真分析,并通过实验进行了验证。结果表明:所提出的自调谐压电振子可实现f~2.1 f范围内的调谐。同时通过调节合适的占空比,调谐装置可以实现自给自足。在休眠时间为411 s以上的条件下,可以实现最大频率范围内的调谐,并且能量收集效率在40%以上。此外,在充电时间和激励加速度相同、激励频率不同的条件下,与无调谐压电振子相比,有调谐装置的压电振子的充电效率提高了223%。

Under the traditional cantilever fixed mode,the frequency band of piezoelectric vibrators is narrow,which has the problems such as poor environmental adaptability and low power generation efficiency.Therefore,a broadband self-tuning piezoelectric vibrator is proposed by changing the fixed position.The tuning model is established,and then the power generation performance of the piezoelectric vibrator at different fixed positions is simulated and analyzed.It is verified by experimental method.The results show that the proposed self-tuning piezoelectric vibrator can achieve tuning in the above range of f~2.1f.At the same time,by adjusting the appropriate duty cycle,the tuning device can achieve self-sufficiency.When the sleep time is more than 411 s,the tuning in the maximum frequency range can be realized,and the energy collection efficiency can reach more than 40%.In addition,when the charging time and excitation acceleration are the same,but the excitation frequency is different,the charging efficiency of the piezoelectric vibrator with the tuning device is improved by 223%compared with that without tuning piezoelectric vibrator.