MATHEMATICAL MODEL OF ELECTRO-MECHANICAL VIBRATION TRANSDUCERS BASED ON THE LEVITATION EFFECT

Abstract

At present, one of the urgent problems in the energy and industry is to improve the reliability of the operation of various equipment. An effective method for increasing the reliability of equipment is diagnosing the state of machines and predicting their performance. Vibration control methods are widely used to diagnose rotary rotating machines. By the nature of the vibration process of the machine, it is possible to determine the degree of wear and, accordingly, the technical condition of the machines. In measuring technology for diagnostics of low-speed equipment with rotation frequencies of a unit of Hz, for example, hydroelectric generators of hydroelectric power plants, inertial electromechanical converters are used. The latest developments of such converters use an electromagnetic suspension with parametric feedback, which allows you to control the rigidity of the oscillatory system. However, for centering the moving part in electromechanical converters, flexible guides are used, which are sources of dry friction, which complicates the simulation of measurement processes and limits the sensitivity threshold to a minimum. In addition, flexible guides limit the frequency range of the converters. Currently, the most promising direction for solving this problem is the levitation effect, which allows you to completely exclude mechanical contact and, accordingly, reduce the sensitivity threshold of the transducer. From the analysis of literary sources, it follows that there are relatively few publications in this area. This article provides an analysis of existing vibration transducers and proposes a mathematical model of the magnetic levitation system, taking into account the influence of the electromagnetic force nonlinearity, as well as a method for selecting the feedback control unit parameters to stabilize the mass position of the vibration sensor.