Study of the influence of nonlinearities on parametric oscillations of electromechatronic systems

Abstract

In the article The analysis of parametric oscillations in electromechatronic systems and the influence of nonlinearities on them caused by physical properties of the elements and design features of the system.

It has been shown that Real electromechatronic systems are characterized by the presence of various nonlinearities. Factors that render a mechanical system nonlinear include nonlinear forces arising during the operation of such a system and its variable parameters. It has been established that parametric oscillations, caused by periodic or quasi-periodic changes in the system's parameters over time, occupy a special place among the dynamic phenomena occurring in electromechatronic systems.

The article discusses the effect of parametric resonance, which is a manifestation of dynamic instability in a system, where small disturbances can lead to significant changes in the system's motion. Consequently, any random disturbance over a sufficiently long period of time can lead to emergency consequences. Nonlinear factors in a mechanical system with periodically changing parameters manifest themselves primarily in zones of parametric resonance.

The authors present the concept of self-oscillations, which can occur in nonlinear systems in the absence of a periodic disturbing force, and, as an example, consider quasi-harmonic frictional self-oscillations. Suppressing frictional self-oscillations is a crucial engineering challenge, as they complicate the precise stopping of a working element and disrupt the smoothness of its movements.

A unified structural diagram for any type of electromechanical electric drive system, its parameters, and a mathematical model are provided.

The electromechanical system was simulated in the MATLAB/Simulink environment in accordance with the structural diagram with the given parameters.

The processes of development of self-oscillations in the considered circuit at a given speed for three variants of the studied load characteristics are obtained.

The dependences of the velocities of the first and second masses, the elastic force and resistance on the second mass, and the dynamic force on time are presented. It is established that the implementation of computer -integrated adaptive and robust control systems, taking into account the presented studies of nonlinear effects and parametric oscillations, ensures the coordination of the dynamic modes of the electromechatronic system with the requirements of a specific technological process. This reduces the influence of unwanted oscillatory modes and improves the stability and accuracy of actuator control.