Резонансный электромагнитный вибровозбудитель колебаний с обратной связью

Abstract

A number of modern technological processes can be significantly intensified due to the use of vibrations with a wide range of oscillation frequencies and amplitudes. In many cases, electromagnetic vibration exciters (EMVE) can serve as the most effective vibration source. Direct conversion of electric energy into mechanical vibration energy opens the possibility for developing devices controlled by electrical methods. However, the oscillatory processes in the circuits containing electromagnetic exciters have been studied to an insufficient extent as applied to vibration engineering. This is connected with the complexity of the effects caused by the nonlinearity of vibration exciter electromagnets and power source on the vibration processes, i.e., a nonlinear dependence of the vibration amplitude and phase on the system parameters and a nonlinear dependence of inductance from the armature displacement. The results from theoretical and experimental studies of oscillating electromechanical systems (EMC) built on the basis of an EMVE with feedback, and the development of methods for analyzing resonant EMVE circuits with a view to obtain the optimal characteristics in low-frequency oscillation modes (LFO) demonstrate the possibilities of economically efficient consumption of electric energy and the performance of the EMVEs used in different industry branches. With the introduction of feedback proportional to the control frequency and the output voltage amplitudes of the EMVE power supply source, it becomes possible to automatically adjust the vibration frequency to the resonance frequency of the elastically suspended EMVE load-carrying member for maintaining constancy of vibration velocity amplitudes and, hence, the system performance. To achieve a stable resonance operation mode of the electromagnetic vibration exciter, the voltage proportional in phase between the inverter output voltage and the load-carrying member motion speed are analyzed. The study results have shown that, owing to the feedback effect that adjusts the driving frequency in phase toward tuning to resonance, a rational EMVE operation mode can be secured.