Research of the Effect of the Inverter Resonance Frequency Skip Function on the Operation of a Vibration Stand in Acceleration and Braking Modes

Vibrational systems of directional vibrations based on asynchronous vibration motors are currently widely used in practice. However, they, as a rule, work in the resonance zone of the frequency response of the vibration stand. Therefore, when accelerating and braking the vibration motors, the vibration stand passes the resonance frequency, which leads to a sharp increase in the amplitudes of the oscillations, which are unacceptable from the point of view of normal operation. In order to study the test product at different frequencies, the vibration motors are controlled by a frequency converter. The purpose of this article is to determine the effect of the inverter resonance frequency skip function on the operation of a vibration stand in acceleration and braking modes. To achieve this goal, the equations of motion of a vibration table driven by two asynchronous unbalanced vibration motors are considered. A mathematical model of an asynchronous unbalanced vibration motor with scalar frequency control is presented. Based on the equations considered, a simulationn model of the vibrating table for the Matlab Simulink software environment is developed. Computer simulation of a specific vibration table during acceleration and deceleration without using the inverter resonance frequency skip function was carried out. The maximum amplitudes of the oscillations during the passage of the resonance frequency are determined. The developed computational model allows one to generate a setpoint signal for vibration motors taking into account the function of skipping the resonance frequencies of the inverter. Computer simulation showed that the use of the function of skipping resonance frequencies significantly reduces the amplitude of oscillations of the vibrating table, especially when braking the vibration motors. The dependence of the amplitudes of the oscillations during the passage of the resonance frequency is found depending on the skip frequency bandwidth. It is concluded that the use of the inverter resonance frequency skip function favorably affects the operation of the vibration system as a whole, but narrows the possible frequency range of the tested product.