AUTOMATIC CONTROL OF A RESONANT VIBRATION DEVICE WITH ELECTROMAGNETIC DYNAMIC VIBRATION ABSORBER

Modern vibration devices should meet the requirements of high efficiency, accurate reproduction of vibration with specified amplitude and frequency, limitation of the force acting on the foundation. Fulfillment of this requirements is possible only by means of automation system application. So the creating of vibration equipment automatic control systems is an urgent task. A structure of automatic control system of vibration device with electromagnetic drive and electromagnetic dynamic vibration absorber mounted on the intermediate platform is proposed in this paper. The system provides specified amplitude and frequency of vibration by means of electromagnetic vibrator current amplitude and frequency control. Simultaneously it maintains stable resonant oscillation mode by means of vibration absorber suspension stiffness control to provide the maximum efficiency of the device. The feedback control of oscillation amplitude and the resonant frequency of the device is carried out using discrete PI-regulator. Determining of oscillation amplitude and phase is carried out in real time by means of performing the discrete Fourier transform of the vibration sensor output signal. The dynamic model of the system has been worked out and the transients has been researched. The simulation results allow to conclude, that the proposed control system provides required accuracy and has satisfactory stability margin at certain values of PI-regulators coefficients.