悬臂梁式压电振动能量收集系统输出功率的优化研究

摘要

In order to solve the problem of low output power of piezoelectric energy harvesting systems caused by less energy and wide band of ambient vibration ,the method of optimizing the output power of cantilever piezoelectric energy harvesting system with the parallel or series inductance are explored and the influence of different parallel or series inductance to the output power is analyzed .Since the frequency of piezoelectric cantilever is low ,and the matching inductor value is large ,lossless simulated inductor is used in experiment .The theoretical analysis and experiment results show that the maximum output power of resonance can also be obtained at the deviating points with different matching inductance corresponding to different excitation frequencies ,which broadens the operating frequency band and improves the total energy harvesting energy level of the system .When the excitation frequency is 0.8 or 1.2 times of the resonant frequency ,the maximum output power with parallel or series inductance is 26.4 and 18.2 times of that of the purely resistive load .%针对环境振动能量较小、振动源频带较宽导致压电能量收集系统输出功率较低的问题，探究了悬臂梁式结构能量收集系统采用并联或串联电感优化统输出功率的方法和特性，分析了不同并、串联电感值对输出功率的影响．鉴于压电悬臂梁的工作频率较低，匹配电感值较大，采用无损模拟电感进行了实验验证．理论分析与实验结果均表明，在不同的激振频率下对应不同的匹配电感值，在偏离谐振频率附近也可获得与谐振状态几乎相同的最大输出功率，从而拓宽了工作频率，提高了压电振动能量收集系统的能量收集水平．当激振频率分别是谐振频率的0.8和1.2倍时，并联或串联电感获得的最大输出功率分别是无电感纯电阻负载的26.4倍和18.2倍．