Structure and Anti-noise Design and Sensitivity Verification of Piezoelectric Low-frequency Accelerometer

• Main Authors: ZENG,YU-ZHE, 曾于哲
• Other Authors: LIU,YUN-HUI
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/393knm

碩士 === 南臺科技大學 === 機械工程系 === 107 === With the pursuit of speed in 3C products, the confidential industry such as semiconductor manufacturing has become increasingly demanding for vibration. Therefore, the predecessors of this laboratory proposed active vibration isolation platform and piezoelectric low-frequency accelerometer gauge for micro-vibration suppression and measurement. This paper studies the sensitivity prediction analysis and the improvement of anti-noise ability on the second-generation accelerometer of this laboratory. The accelerometer structure uses ANSYS's modal and frequency response analysis to predict the accelerometer mode shape and available bandwidth, and ANSYS and theory predict the sensitivity of the accelerometer. In the piezoelectric analysis of ANSYS, the piezoelectric material is assumed to be a transversely isotropic material using elastic theory to obtain the complete piezoelectric parameters. In the experiment, four kinds of piezoelectric materials were used for the experiment. Finally, the ANSYS analysis and the actual measurement results were compared with the sensitivity calculation, and the sensitivity and the actual relationship of the accelerometer showed the same trend.The environment is full of many noise interferences. The accelerometer uses a charge amplifier to convert the charge into a voltage. This transmission is greatly affected. The general accelerometer puts the charge amplifier into the accelerometer to minimize this effect. Compared with the problem that the commercially available charge amplifier is too large, the self-made amplifier can be used to adjust the size and circuit design. In the experiment, the external environment noise (60Hz) will be reduced according to the way of external noise transmission, using grounding, shielding materials, filtering and changing the signal line type. Finally, the noise is reduced and applied to the accelerometers.