振弦传感器扫频激振与测频方法研究  

Study on Swept-Frequency Excitation and Frequency Measurement of Vibrating Wire Sensor

作　　者：鹿玲[1] 戴学松 姜志学 LU Ling;DAI Xuesong;JIANG Zhixue(School of Software,University of Science and Technology,Anshan 114051,China)

机构地区：[1]辽宁科技大学软件学院,辽宁鞍山114051

出　　处：《自动化仪表》2018年第10期42-45,共4页Process Automation Instrumentation

摘　　要：单线圈振弦传感器主要用于大坝、桥梁及建筑物等各种工程的安全压力监测。与压电等其他传感器相比,其测量压力更加精确,使用寿命更长。这类传感器的应用难度在于如何通过有效的激振方法,使振弦以当前压力下的固有频率振荡,且振荡幅值需达到测量的要求。介绍了一种新的单线圈振弦传感器扫频激振与测频方法,在未找出振弦自激振荡频率前,采用缩短计数时间粗略计算振弦自激振荡频率,以达到快速扫频的效果;在预判将要出现振弦自激振荡频率时,再采用延长计数时间来精确计算振弦自激振荡频率。该方法对有效激振和扫频方式进行了改进,并采取一些有效措施以提高测频精度。实际测量应用证明,该方法稳定、可靠,且精度高。The single coil vibrating wire sensors are mainly used in various safety pressure monitoring in constructions of dams, bridges and buildings and etc. Compared with other sensors such as piezoelectric sensor, the pressure can be more accurately measured, and the service life is longer. The difficulty of the application of the vibrating wire sensors is how to make the vibrating wire oscillate with the natural frequency at the current pressure by effectively exciting method, and the amplitude of the oscillation needs to meet the requirements of the measurement. A new method of swept-frequency excitation and frequency measurement for single coil vibrating wire sensor is introduced. Before the finding of the vibration frequency of the vibrating wire, the method of shortening the counting time to roughly calculate the self-excited oscillation frequency of the vibrating wire can achieve the effect of fast sweeping; when it is predicted that the vibrating wire seff-excited oscillation frequency will appear, the extended counting time is used to accurately calculate the seff-excited oscillation frequency of the vibrating wire. The method has improved the effective excitation and frequency sweeping methods, and adopted some effective measures to improve the frequency measurement accuracy. This method is proved to be stable and reliable and accurate in practical measurement applications.

关 键 词：振弦传感器 双电压扫频激振 粗精接合测频法 单片机 测频精度 

分 类 号：TH812[机械工程—仪器科学与技术] TP212[机械工程—精密仪器及机械]