Research On Vibration Control Technology Of Vibroseis Based On Permanent Magnet Spring

The vibrator is one of the most important equipments currently used in oil and gas exploration,and the vibration isolation control of the vibrator is related to the accuracy and quality of the excitation signal of the vibrator.In the low frequency range below 6 Hz,it is difficult to resist external interference,affect the excitation signal,and cannot meet the needs of high-precision seismic exploration.In order to ensure the operation quality of the vibrator in the low frequency range and even the ultra low frequency band,this paper introduces the negative stiffness structure in the vibroseis vibration isolation structure system,and designs the parallel stiffness isolation system of the positive stiffness spring and the permanent magnet negative stiffness structure.Mainly complete the following work:The design device is mainly composed of three permanent magnets,which are used in parallel with the positive stiffness spring to reduce the dynamic stiffness of the vibration isolation system without affecting the static stiffess.(1)Vibration model analysis of vibroseis.According to the working principle of the vibrator,the forced vibration model of the single-degree-of-freedom system of the vibrator is determined.The influence of the parameters of the vibration isolation system on the vibration isolation effect is analyzed,and the vibration isolation efficiency is calculated.(2)The structure of the permanent magnet negative stiffness spring is realized.The stifffness and magnetic force changes of permanent magnet springs at different positions are analyzed.Using finite element software,the relationship between the distance between permanent magnets and its stiffness is analyzed.The mechanism of permanent magnet negative stiffness spring formation is studied.The permanent magnet repulsion spring is used to construct the permanent magnet negative stiffness spring.The calculation proves that the permanent magnet negative stiffness spring is connected in parallel with the positive stiffness spring,which can affect the load of the original vibration isolation system.The vibration isolation performance of the vibration isolation system can be improved.(3)A low frequency vibration isolating isolator is designed.The structure in which the positive stiffness spring and the permanent magnet negative stiffness spring are connected in parallel improves the efficiency of low frequency vibration reduction.(4)Simulation.The feasibility of vibration isolation of the structure in the vibration isolation system is analyzed by Adams vibration simulation.It can be visually seen through Lab VIEW simulation that the structure has significant vibration isolation effect in the vibration isolation of the vibrator.The simulation results show that the vibration isolation scheme makes the vibration isolation efficiency of the vibroseis vibration isolation system significantly improved.Although the low-frequency vibration isolators have many advantages,including low cost,energy saving and environmental protection,the feasibility of the practical application of the vibration isolation structure needs further experimental verification.