基于压电简支梁拉伸调频的旋磁发电机

Rotary Magnet-coupled Generator with Frequency Adjustment Using Extensions of a Piezoelectric Simply-supported Beam

为提高旋转式压电发电机的可靠性以及拓宽其有效转速带宽,提出了一种基于压电简支梁拉伸调频的旋磁发电机。介绍了所提发电机的结构原理,研究了动磁铁数量、压电振子预压量等因素对发电机发电性能及固有频率的影响规律。试验结果表明:发电机在转速范围内存在多个使电压出现峰值的最佳转速,各个最佳转速的数值随预压量的增大而增大,且最佳转速的数量随动磁铁数的增加而减少;调节预压量可拓宽发电机的有效转速范围,如动磁铁数为8时,当预压量为0时,发电机仅在几个谐振点达到电压要求,当预压量为1 mm、3 mm、5 mm时,有效转速范围分别扩大至321~768 r/min、160~1000 r/min、123~1000 r/min;该发电机固有频率可在37.33~89.60 Hz范围内进行调整,对应的转速调节范围为280~2632 r/min。

To improve the reliability and broaden the effective speed bandwiths of rotary piezoelectric generators,a rotary magnet-coupled generator with the frequency adjustment using the extensions of a piezoelectric simply-supported beam was presented.The structures and working principles of the proposed generator were demonstrated,the influences of the number of rotating magnets and the precompression amounts of the piezoelectric beam vibrator on the power-generation performance and natural frequency were studied.The testing results show that there are multiple optimal speeds enable the generated voltage to reach the peak.The values of all the optimal speeds are increased with the increasing of precompression amounts,and the numbers of optimal speeds are decreased with the increasing of the number of rotating magnets.The effective speed ranges may broaden through adjusting the precompression amounts.If the number of rotating magnets is as 8,when the precompression amount is as 0,the generator may meet the voltage requirements only at several resonance points.However,when the precompression amounts are as 1 mm,3 mm,5 mm,the effective speed ranges may be broaden to 321~768 r/min,160~1000 r/min,123~1000 r/min,respectively.The natural frequency of generator may be adjusted in the range of 37.33~89.60 Hz,and the corresponding speed range is as 280~2632 r/min.