With the development of Internet of thing（ IoT）

multi-node sensor power supply has become a critical problem

since low frequency vibration exists generally in environment

use piezoelectric cantilever beam structure and establish electrical model of piezoelectric cantilever beam structure. ANSYS simulation is carried out and obtain voltage of 76 V

which is approximately equal to the theoretical value of the model

which verifies the correctness of model. Then continue to study the relationship between influence of geometry size of piezoelectric cantilever beam on natural frequency. The longer the oscillator and mass are

the lower the frequency are. Collect low-frequency vibration environment energy from environment and provide theoretical basis for design of sensor supply device.