液位检测光纤传感器系统设计

系统采用双膜盒作为水压的敏感元件,将光纤位移传感器用于检测膜盒随水压变化引起的形变.系统的信号处理电路包括光信号前置放大电路、带通滤波电路、真有效值转换电路,采用16位超低功耗的混合信号处理器MSP430作为数据处理模块.实验结果表明:系统可以测量0～181.0 mm的水面液位变化,分辨率为0.7 mm.增加膜盒的数量可以提高系统的分辨率.

Design of liquid level detecting based on optical fiber sensor

By taking a twin diaphragm box as the sensing component for underwater pressure,a micrometric optical fiber displacement sensor was employed to inspect deformation of diaphragm box with water pressure changing.The signal processing circuit mainly includes signal pre-amplifier,BPF,RMS converting circuit,and 16 Bit MSP430 with ultralow-power consumption.The experimental results indicate that the change of water level from soutis 0 mm to 181 mm can be detected with the resolution of 0.7 mm.The resolution can be improved by increasing the amount of the diaphragm boxes.