Research On Temperature Characteristic And Compensation Method Of Electrochemical Geophone

Seismic exploration is widely used in the research of earth's internal structure,nuclear explosion monitoring,engineering exploration and detection,geological disaster prediction and other fields,and geophone is its core equipment.Electrochemical geophones,based on the principle of inertial sensing technology,use the movement of the ions in the electrolyte to measure the vibration signal.Compared with other geophones,electrochemical geophones have many advantages,such as good low frequency characteristics,high sensitivity,short stability time,etc.,so they have been widely used in many fields in recent years.However,in the actual exploration environment,the change of environment temperature is inevitable,and the electrochemical geophone is greatly affected by the temperature change.The study of the output characteristics of the electrochemical geophone with the change of temperature can reduce the impact of temperature on the output of the electrochemical geophone and ensure its stable operation,which has an important reference value for the practical application of the electrochemical geophone.According to the working principle of the electrochemical geophone and the analysis of the specific experimental data,the temperature characteristics of the geophone are studied and the corresponding compensation methods are proposed,the main work is as follows:(1)In this paper,the mechanism of detecting vibration signal by electrochemical geophone is analyzed,and the factors that affect the parameters of electrochemical geophone are analyzed in detail,including electrochemical reaction rate of electrolyte,thermal noise of electrolyte,elasticity of elastic rubber mold,viscosity and conductivity of electrolyte.(2)The temperature characteristics of electrochemical geophone are studied.The temperature lag effect of the electrochemical geophone is tested by using the ultra-low frequency vibration calibration system.The output sensitivity and distortion of the electrochemical geophone at different temperatures are measured and calibrated,and the performance of the magnetoelectric geophone is compared.Based on the theoretical and experimental analysis,the temperature compensation formula of electrochemical geophone is calculated.Through the simulation of the influence of temperature on the electrochemical reaction rate,the temperature compensation formula is optimized.The optimized compensation formula can control the sensitivity change rate at 8%.(3)using phase change energy storage material to absorb and release energy in the process of temperature change,and the unique three-dimensional network structure of porous foam copper,the phase change energy storage shell of electrochemical geophone is produced,which can reduce the sensitivity of electrochemical geophone 20%.Meanwhile,the effects of pore density,porosity and thickness of porous copper foam on the temperature compensation effect of the shell were also tested.(4)The temperature compensation control system of the electrochemical geophone is designed.The temperature range of the compensation system is set to adjust and compensate the temperature.After using the temperature compensation control system to control the temperature,the output sensitivity curve is relatively stable.At the same time,combining the temperature compensation control system with the phase change material shell,the phase change material shell can reduce the power consumption and noise of the temperature compensation control system,and greatly improve the temperature compensation effect.In the temperature range of 5?-20?,the sensitivity variation rate can be controlled at 10%.