Optimization Design Of Seismometer Based On Concentric Ring Magnetic Field Structure

As an instrument for measuring surface movement,seismic instruments are widely used in seismic signal monitoring,earthquake prediction and early warning,oil and gas resource exploration and mine safety.The seismometer is the key equipment to monitor the vibration signal,and its performance directly affects the quality of seismic signal acquisition.Magnetoelectric seismometer is widely used in the field of earthquake monitoring because of its simple structure,easy assembly,stable and reliable performance,low cost and easy networking.Magnetic field structure is an important energy conversion place in magnetoelectric seismometer.The performance of transducer will seriously affect the quality of seismic wave acquisition,recording and processing.At present,the magnetoelectric seismometer has the bottleneck problems of low sensitivity and high distortion.Therefore,this paper proposes a magnetoelectric seismometer based on concentric ring magnetic field structure and double magnetic ring magnetic field structure.The main research contents include:(1)In order to improve the sensitivity and distortion of magnetoelectric seismometer,a magnetoelectric seismometer based on concentric ring magnetic field structure is designed,which improves the uniformity of magnetic induction intensity and magnetic flux distribution.The ANSYS Space Claim software is used to establish the concentric ring magnetic field structure model,and the spatial magnetic induction intensity of the magnetic field structure is numerically derived.The influencing factors of its key structural parameters are analyzed,and the parameters of the magnetic field structure are optimized,which provides theoretical support for subsequent research work.(2)In order to further broaden the uniformity range of the concentric ring magnetic field structure and ensure the large amplitude vibration of the seismometer coil,a magnetoelectric seismometer based on the double magnetic ring magnetic field structure is designed.The simulation model of the double magnetic ring magnetic field structure is established by ANSYS Space Claim software,and the key parameters of the magnetic field structure are optimized and analyzed.The static and transient characteristics of the seismometer magnetic field structure model are simulated and analyzed by Ansoft Maxwell software,which improves the uniformity of the seismometer magnetic field structure and reduces the distortion of the seismometer.The engineering prototypes of the concentric ring magnetic field structure and the double magnetic ring magnetic field structure of the seismometer are developed.The magnetic field air gap magnetic induction intensity test system is designed,and the performance index of the seismometer magnetic field structure is tested experimentally.The experimental results show that the air gap magnetic induction intensity of the concentric ring magnetic field structure is 833 m Tesla,which is 119 %higher than that of the traditional magnetic field structure before optimization.The uniform range of the magnetic field is 7.6 mm,broadening by 16.9 %.The air gap magnetic induction intensity of the double-ring magnetic field structure is 928 m Tesla,which is 144 % higher than that of the traditional magnetic field structure.The uniform range of the magnetic field is 8.6 mm,which is widened by 32.3 %,and the sensitivity and distortion of the seismometer are improved.