Excitation method of vibrating wire sensor

Abstract

An excitation method of a vibrating wire sensor mainly comprises the following operating steps: performing single excitation for exciting coils of the vibrating wire sensor by an intermittent excitation mode to obtain a resonant frequency measured value f1 with low precision; calculating statistical characteristics of vibration signals during various periods, and inspecting the statistical characteristics; exciting the exciting coils of the vibrating wire sensor by adopting a signal with the frequency being f1 and stopping excitation after vibrating wire resonance, or performing frequency-sweep excitation at the position of a narrower bandwidth near the frequency f1; and finally processing signals from vibration pickup coils, and measuring the signal frequency to obtain a measured value f2 as an exact value of vibrating wire resonance frequency. The excitation method of the vibrating wire sensor has the advantages of fast starting of vibration, large amplitude, shortened detection time, improved working efficiency, improved excitation reliability and improved measuring precision. The excitation method of the vibrating wire sensor is applicable to observation on stress strain, deformation, seepage, liquid level, temperature and the like of the projects such as reservoir dams, bridges, foundation pits and the like.

Description

technical field [0001] The invention belongs to the category of sensor measurement, and relates to a vibrating wire sensor measuring system, in particular to a vibrating method for a vibrating wire sensor. Background technique [0002] Since the output of the vibrating wire sensor is a frequency signal, the influence of factors such as the resistance, inductance and capacitance of the cable can be ignored during the transmission process, and it has the advantages of strong anti-interference ability and easy long-distance transmission, so it is widely used in reservoir dams In the monitoring of stress and strain, deformation, seepage, liquid level, temperature, etc. of projects such as bridges, foundation pits, etc. The general working principle of the vibrating wire sensor is: the steel string is placed in the magnetic field, and after the steel string is excited by a certain method, the steel string will vibrate, and the vibrating string will move in the magnetic field to c...

AI Technical Summary

Problems solved by technology

[0004] The traditional intermittent excitation method has poor excitation effect, small excitation amplitude and short vibration duration, which is not conducive to picking up and processing the vibration signal of the vibrating wire, which affects the measurement accuracy

The frequency sweep excitation method has the advantages of reliable excitation, but because of the wide frequency range of frequency sweep excitation, it needs a longer excitation time, and it will cause the amplitude of the vibrating wire that has already resonated to decrease at the end of the frequency sweep. attenuation

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