Study On Large Electric Vibration Table Dynamics Analysis And Numerical Simulation

With the rapid development of aviation, environmental vibration test equipmentwhich is used in aerospace, electronics industry, a variety of test spacecraft,instruments, equipment, environmental vibration test is also growing. Shaking tablehas been widely used in the identification of equipment performance assessment anddynamic strength as an effective means to simulate the vibration environment, testingequipment reliability and dynamic strength. Various types of vibration, electricalvibration was widely used because of band width, carrying a wide range of waveform,easy to control and many other advantages.The main subject of study are simplified electrodynamic shaker mathematicalmodel, established kinetic equation and the equations of control system in theory.Obtained numerical solution of natural frequency through kinetic equation. Obtainedresonant frequency and the system main anti transfer function with frequencyvariation by control system equation. Through numerical simulation method and theapplication of large scale analysis of finite element software ANSYS, analyzed modaland harmonic response of the electrodynamic shaker core. Study on shaking tablemagnetic system numerical simulation obtained the distribution of the magneticinduction. Discussed the impact of structural parameters on the air gap magnetic fielddistribution. Obtained the relationship of current loaded and the table accelerationresponse by structure and magnetic field coupling numerical simulation. Researchwith main achievements include the following aspects.(1) Established the kinetic equation, equations of circuit system and controlsystem equation. Theoretically obtained the natural frequencies of the four-degreesfreedom simplified dynamic model. Impedance characteristic expression: includingcircuit impedance and sports impedance. Established control equation by circuitequivalent analogy. Further simplified the model for the frequency domain, obtainedthe relationship with the system transfer function and frequency variation.(2) Established the finite element model of20ton electric vibration table.Numerical simulation analyzed the modal analysis, harmonic analysis and surfaceunevenness of the lateral vibration frequency dependent. The dynamic modal and thevibration response were reflected accurately, and were compared with experimentaldata.(3) Established the magnetic system as20ton electric vibration table structuresize model. According to the magnetic material, the range of excitation currentexcitation coil turns, numerical simulated a maximum working magnetic fieldstrength of air gap and the air gap magnetic field distribution. Discussed the effect ofmagnetic structure size to the air gap magnetic field. (4) Established vibration table magnetic structural coupling model. Simulated theelectromagnetic force on moving coil and dynamic structural analysis as the loading force.Obtained countertops displacement over time changes in the law by dynamic structuralanalysis.