同轴电缆电容感测式水位传感器设计

Design of Water Level Sensor Based on Capacitance Sensing Mechanism of Coaxial Cable

针对传统水位传感器在恶劣水质条件下存在可靠性不高、测量精度低的问题,文中提出一种同轴电缆电容式水位测量方法,以特殊构造同轴电缆作为传感敏感元件,研究其将水位转为电容参数的传感机理,采用PCAP01电容数字转换方案,运用拟合与水位标定算法,设计了同轴电缆电容感测式水位传感器。实验结果表明,传感器在0.1～1 m水位范围内的测量精度可达0.01 m,稳定性良好,可应用于恶劣水质环境下的水位测量。

Aiming at the problem that traditional water level sensors has the problem of low reliability and measurement accuracy of traditional water level sensors in poor water quality,this paper presented a capacitive water level measurement method with the special coaxial cable as a sensor sensitive element.By studying the sensing mechanism with which it transforms water level to the capacitance parameter and application of fitting and water level calibration algorithm,a capacitance-to-digital sensing water level sensor was designed with PCAP01 capacitance-to-digital conversion(CDC) processor.Experimental results show that with the water level calibration algorithm,the measurement accuracy of the sensor is 0.01m within the scope of 0.1m to 1m and its stability is good,which means that it can be applied to the water level measurement in the bad water environment.