Detection And Analysis Of Low Frequency And Weak Vibration Signals Based On Magnetic Levitation Effect

Different from the traditional relative vibration measurement method,the application of absolute vibration measurement method has always been concerned,and the detection of low frequency and weak vibration signal is an important application field of absolute vibration measurement method.This paper designed the magnetic levitation effect as the main body of low-frequency and weak vibration signal detection system,belongs to the absolute vibration system,suspension module shell without mechanical connection and measurement system,application of photoelectric displacement sensor calibration suspension position,make the suspension module smaller energy loss and improve the testing system of static characteristic and dynamic characteristic,has higher sensitivity.The measuring control circuit controls the current in the enameled wires of the electromagnet by detecting the output voltage of the photoelectric displacement sensor,thus forming a closed-loop control.Therefore,it is of great significance to use the magnetic suspension effect to detect and study the low-frequency and weak vibration signals.In this paper,a vibration measurement system based on maglev effect is studied,which consists of electromagnet,suspension module,photoelectric displacement sensor and signal processing circuit.Firstly,the principle of each functional part is modeled mathematically,the electromagnetic force equation and the dynamic equation are derived,and the control circuit of the maglev system is determined according to the operating characteristics of the photoelectric displacement sensor.According to the suspension position established by the mathematical model,magnetic field simulation software ANSOFT is used to simulate the magnetic field line and magnetic induction intensity distribution in the suspension process,and theworking area of the maglev module is preliminarily planned,which theoretically verifies the feasibility of vibration measurement of the system.Secondly,a simulation circuit is built for the magnetic suspension vibration subsystem.By adding low-frequency and weak vibration signals,the minimum operating frequency and minimum operating acceleration of the system are determined theoretically,and the measured range of frequency and acceleration of the system is demarcated.Thirdly,the natural frequency signal,maglev vibration signal and external noise are simulated through wavelet analysis.Then the low-frequency vibration signal experiment is applied to the standard vibration experiment platform to verify the low-frequency vibration measurement reliability of the system.Finally,the application of the maglev system is studied,and the actual operation of the elevator is measured.The experimental results show that the maglev system has a good detection ability for the weak vibration signal in the actual application,and the maglev effect vibration measurement system will have a better application in more low-frequency and weak vibration signal detection occasions.