光电工程, 2015, 42 (5): 75, 网络出版: 2015-09-08
液滴分析仪光电传感器的改进
The Improvement of Droplet Analyzer Photoelectric Sensor
液滴分析技术 光纤传感器 电容传感器 液滴指纹图 droplet analysis technology optical fiber sensor capacitance sensor AD7747 AD7747 droplet fingerprint
摘要
针对液滴分析仪光纤、电容传感器多次测量重复性不高, 影响液滴分析测量精度的关键问题, 重新设计了传感器结构, 在电容环形极板外部增加屏蔽结构。采用数字电容信号测量法代替原有激励模拟测量方法, 电容传感器测量极小值标准差为 0.001 7 pF, 极大值标准差为 0.002 4 pF。改进光纤信号测量电路, 利用无限增益低通滤波器避免由于放大倍率过高引起的自激震荡, 光纤传感器测量峰值标准差为 0.019 9 V, 提高了液滴分析仪测量精度。
Abstract
For the key problem of droplet analyzer optical fiber and capacitance sensor poor measurement repeatability which impact droplet analysis measurement accuracy, the sensor structure was redesigned by increasing shielding structure in the external of capacitance sensor annular plate.Digital capacitance signal measurement method was used instead of excitation type analog measurement method.The minimum and maximum standard deviations measured by capacitance sensor are 0.001 7 pF and 0.002 4 pF.The optical fiber signal measurement circuit was improved, and infinite gain low-pass filter was used which avoided self-excited oscillation caused by high magnification.The peak standard deviation measured by optical fiber sensor is 0.019 9 V, and the droplet analyzer accuracy is improved.
姚尧, 裘祖荣, 樊玉铭. 液滴分析仪光电传感器的改进[J]. 光电工程, 2015, 42(5): 75. YAO Yao, QIU Zurong, FAN Yuming. The Improvement of Droplet Analyzer Photoelectric Sensor[J]. Opto-Electronic Engineering, 2015, 42(5): 75.