For the purpose of collecting and converting vibration and noise energy existing in the environment into energy suitable for microelectronic system. A cantilever beam energy acquisition device is designed by using PZT—5 H piezoelectric plate

and the first three modes

mode shapes and size factors of the piezoelectric vibrator are analyzed by finite element method

an experimental bench is built for experimental research on its energy acquisition efficiency. The results show that the natural frequency of piezoelectric vibrator is inversely proportional to its length and directly proportional to its thickness and width. When the first-order natural frequency of the system is equal to or close to the external excitation frequency

the energy acquisition efficiency will reach the maximum. By changing the natural frequency of the piezoelectric vibrator

the external vibration source can be better matched

thus improving the energy acquisition efficiency and providing theoretical basis for designing the piezoelectric energy acquisition device to supply power to the MEMS.