Vibration Energy Collection System Based On One-dimensional Piezoelectric Metamaterials

Vibration energy mostly exists in the form of elastic waves in mechanical structures,and has the characteristics of low frequency and broadband.In view of the above characteristics,this paper designs a piezoelectric metamaterial structure to collect broadband and low frequency vibration energy.By studying the output open circuit voltage,output power and other parameters of the piezoelectric device to anal yze its energy collection abilit y,and explore its practical engineering Possibility in application.The main research work of this paper is as follows:The working principle of the piezoelectric metamaterial energy harvesting device is anal yzed and the structure of the energy harvesting device is designed.A model of elastic wave propagation in the piezoelectric metamaterial structure is established.For this model,its vibration response is based on the Rayleige-Ritz method Solve the elastic wave propagation response function in the piezoelectric metamaterial structure through finite element simulation,and get its elastic wave propagation characteristics.The band gap of the piezoelectric metamaterial structure is solved and anal yzed by the finite element method.The modal shape is obtained through simulation and the energy distribution of t he piezoelectric metamaterial's cell structure is anal yzed.Finall y,the controlled variable method is used to anal yze the influence of geometric parameters and material parameters on the band gap characteristics of the piezoelectric metamaterial.The anal ysis and calculation results It can provide a theoretical basis for the design and optimization of piezoelectric metamaterial structures for broadband and low-frequency vibration energy harvesting.Use the output open circuit voltage as an indicator to stu dy the energy harvesting abilit y of the piezoelectric metamaterial structure,simulate and experimentall y analyze the energy output capabilit y of the piezoelectric metamaterial structure using different piezoelectric materials,and compare the experimental results with the numerical results to prove The validit y of the numerical calculation results is verified.Then,comparative experiments are conducted to anal yze the influence of the local resonance unit and its band gap characteristics on the energy harv esting efficiency of the piezoelectric metamaterial structure.The test results show that the piezoelectric metamaterial structure can effectivel y absorb the elastic wave vibration energy in a specific frequency range and convert it into electrical energy.Under the external excitation frequency of 110 Hz?210Hz,the piezoelectric metamaterial structure was connected to a 9.2M?load resistor to analyze the output power and power densit y.The results show that the piezoelectric metamaterial structure containin g the local resonance unit has a good energy harvesting abilit y in the range of its band gap frequency.The highest output power is 8.57n W and the highest power density is 0.779?W/cm~3.Finall y,a charge and discharge test was performed on it.The voltage a cross the 100?F capacitor can reach 0.315V,which proves that the energy collected by the piezoelectric element after optimization can be stored and utilized.