高灵敏度自动标定无线漏水监测系统设计

Design of high-sensitivity wireless water leakage monitoring system with automatic calibration

针对光纤耦合传感器易受外界光源和柔性形变等影响,导致折射率变化从而使上位机产生误判的问题,文中提出一种可自动标定的高灵敏度无线漏水监测系统。该系统选用侧边抛磨光纤折射率传感器,通过光电转换器将光纤传感器上的光功率转换为微弱电流信号,在STM32单片机控制下实现微弱电流的放大滤波器处理和A/D采集处理。然后采用无线通信模块CC2530将下位机采集存储的数据传输至LabVIEW上位机进行处理和显示。该上位机系统可根据采集初始值对漏水判断阈值自动进行动态标定,以降低漏水监测传感器的误检率。此外,文中系统利用ZigBee无线传感器网络技术构建大规模漏水监测组网,减少了有线网络布线和资源浪费。实验结果表明,文中所提漏水检测系统的灵敏度高、抗干扰能力强,能够实时检测漏水位点的状态。

In allusion to the problem that the optical fiber coupling sensor is easy to be affected by external light source and flexible deformation,resulting in the change of refractive index,which makes the upper computer bring misjudgment,a highsensitivity wireless water leakage monitoring system with automatic calibration is proposed in this paper. In the system,the sidepolished optical fiber refractive index sensor is selected,the optical power of the optical fiber sensor is converted into the weak current signal by means of the photoelectric converter,and the processing of the weak-current amplification filter and AD acquisition are realized under the control of the single-chip microcomputer STM32. The wireless communication module CC2530is used to transmit data collected and stored by the lower computer to the upper computer with LabVIEW for processing and display. The upper computer system can automatically and dynamically calibrate the water leakage judgment threshold according to the collected initial value,which can reduce the false detection rate of the water leakage monitoring sensor. In the system,the ZigBee wireless sensor network technology is used to construct the large-scale water leakage monitoring networking,which can reduce the wired network wiring and resource waste. The experimental results show that the water leakage detecting system has high sensitivity and strong anti-interference ability,and can detect the state of water leakage points in real time.