Дослідження коливань у механізмах з асинхронним приводом

Abstract

Наведено аналіз коливних явищ, які виникають при розгоні асинхронного привода механізму. При проведенні розрахунків використано двомасову динамічну модель. Зв’язок між зосередженими масами механізму – пружно-в’язкий. Показано, що нехтування у розрахунках електродинамічними перехідними процесами двигуна (використання статичної механічної характеристики) може призвести до резонансу та перевантаження елементів механізму динамічними зусиллями. Вказано способи забезпечення відсутності резонансу в механізмах, обладнаних асинхронним приводом та наведено основні напрямки подальших досліджень.

The analysis of oscillatory phenomena that occur during acceleration of asynchronous drive mechanism is presented in the article. In the calculations two-mass dynamic model was used. Generalized coordinates of the mechanism and its drive are adopted to be angular. The constraint between localized mass of mechanism is elastic- viscous. The equation of motion of a dynamical system with help of the numerical methods has been solved. The maximum dynamic moment in the elastic-viscous constraint of mechanism was found. The influence of the values of the system parameters on the value of the dynamic forces in its elements is shown. In the research the dynamic and static mechanical characteristics of the engine are used. Dynamic characteristic is given in the form of equations in orthogonal coordinates fixed α and β. It is shown that the neglection of in the calculation of electrodynamic transients of engine (use of static mechanical characteristics) can lead to resonance and overload of elements of the mechanism of dynamic forces. The conditions of resonance in the mechanism, associated with the coincidence of the natural oscillation frequencies of the mechanism with one harmonic frequency electromagnetic torque have been investigated. It is shown that in the resonance appearance the width of the resonance zone, the attenuation coefficients of pulsating component of the electromagnetic torque and damping coefficients of the mechanical parts of the system are of great importance. Some considerations about the work of distributed parameter systems with an induction engine have been stated. The methods to ensure the absence of resonance in the mechanisms with asynchronous drive have been presented. Basic directions of further researches are listed. In order to establish the degree of danger of resonance for systems with distributed parameters it is necessary to carry out the numerical integration of differential equations of motion of the system and to find the maximum force in the elements of machines and mechanisms. Analytical dependences presented in the article are also shown in the graphical form.