驱替实验压力信号采集与放大电路设计

In this paper, the design of the acquisition and amplification circuit for weak pressure change signals in the petroleum displacement experiment aims at the technical difficulties in the acquisition of weak pressure change signals in the petroleum displacement experiment. A design scheme of a small-signal amplification circuit based on diffused silicon pressure sensors and high-precision operational amplifiers is proposed. By adopting the constant current source power supply technology and the three-operational amplifier instrument amplifier structure composed of TLC2652 and OP2177, the high-precision amplification and noise suppression of microvolt-level pressure signals have been achieved. Experiments show that this circuit can amplify the microvolt level signal to the millivolt level, and the output voltage range is adapted to the subsequent digital processing requirements. This design provides an effective solution for micro-pressure difference monitoring in the exploitation of low-permeability reservoirs, which is of great significance for improving the accuracy and reliability of oil displacement experimental data.