耐高压FBG压力传感器实验研究

为了提高光纤Bragg光栅（FBG）的压力灵敏度以实现油气井下高压传感的测量要求，设计了一种以薄壁筒为衬底外加保护套的耐高压FBG传感器。将FBG沿着弹性筒的轴向用高温胶固化在筒的内部。由于外界油压将引起弹性筒轴向压缩并传递到FBG上引起FBG波长的变化，测量FBG波长的变化即可得到外界压力的变化。理论得到传感器的压力响应灵敏度为-0．035nm／MPa；0-40MPa压力范围内压力实验测得传感器压力响应灵敏度为-0．0339nm／MPa，线性拟合度为0．9997，理论和实验符合得很好。结果表明：该传感器性能稳定，线性度和重复性好，可以用于油气井下高压的实时测量。

Experimental study of high-pressure resistant FBG pressure sensor

In order to improve pressure sensitivity of fiber Bragg grating（FBG） sensor so that it can be used in oil and gas under the shaft high-pressure sensing measurement requirement, a high-pressure resistance FBG sensor based on thin-wall elastic cylinder with protective sleeve is designed. Along the axial direction of the elastic cylinder, FBG is sticked to the inner surface by high-temperature giue. Because the change of oil pressure outside the elastic cylinder results in axial compression and the strain is transmitted to FBG, and causes wavelength change of FBG, so ambient pressure change can be measured by testing wavelength change of FBG. The pressure sensitivity by theoretical calculation is --0. 035 nm/MPa, in pressure range of 0 - 40 MPa, pressure response sensitivity is -0. 033 9 nm/MPa, linear degree is 0. 999 7, the theoretical calculation results are consistent with experimental results. Results reveal that performance of the sensor is stable, linearity and repeatability are good, this kind of pressure sensor can be used in real-time high-pressure measurement of oil and gas under the shaft.