To solve the optimization problem of bimorph cantilever piezoelectric energy harvester

the Roundy mathematical model is modified

where difference between the deflection at the center of the proof mass and that at the end of the cantilever is considered. By using the finite element software of ANSYS

modal analysis and harmonic response analysis of energy harvester model are carried out. The results show that modified model is more accurate than Roundy model in predicting the first order natural frequency and output voltage of the harvester when the length of mass block grows. Influence law of mass block shape and load on energy harvester output characteristics is studied

it is found that when the weight of mass block is constant

mass block with a higher center of mass will make the energy harvester have a better generating capacity

and the result has reference significance for structural optimization of the piezoelectric energy harvester.