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The paper deals with a workflow of a proportional pressure modulator equipped with a linear electric motor of electromagnetic type (LEMET). A schematic diagram consisting of a power supply and control system has been constructed to determine the performance of LEMET. The power supply system is a self-contained half-bridge inverter. The converter input is supplied with 12 V DC voltage. The motor phase is powered by an inverter which includes transistor switches and diodes. The control system of the autonomous inverter consists of two channels – a current limiting channel and a linear transfer channel. The study is based on the results of numerical and simulation modeling of LEMET workflows. Numerical simulation is performed and investigated by a finite element method in the FEMM environment. Geometry of the LEMET model lies in the region of air with an electromagnetic permeability of 1. An initial radius of the grid generation for the working gap area is 0.5 mm, while for other areas an adaptive generation method has been applied. In order to determine a continuous power function at any point within a current variation interval i and a displacement x current linkage and electromagnetic force functions have been approximated by polynomials use of the Curve Fitting application. The simulation LEMET model of a proportional modulator has been built in the MatLab Simulink environment. The implicit Runge-Kutta method using the secondorder inverse differentiation formulas with a variable step has been applied for solution of a mathematical model in the MatLab Simulink system. The equation of an electrical circuit for an inductor motor phase has been compiled according to the second law of Kirchhoff. The LEMET traction characteristics have been obtained by moving a locking and adjusting element (LCE) from 0 to 6 mm in steps of 1 mm while changing the MMF in the winding from 0 to 2 A in steps of 0.1 A. It has been established that in order to move the LCE by 6 mm with the speed of 40 mm/s with a resolution of 0.15 mm, the maximum value of the current in the LEMET winding is equal to 2.5 A. In this case the value of the electromagnetic force is 120 N. This makes it possible to improve an accuracy of the brake drive pressure regulation by 12.3 %. Solutions have been proposed to increase the LEMET speedwork. Characteristics of the engine have been described and numerical parameters of LEMET have been determined in the paper. The developed simulation model allows to investigate functional properties and dynamic characteristics of the proportional modulator with a relative error of 4.07 %.

Abstract.Energy saving and rational use of energy resources is a priority direction for the development of the Ukrainian economy. Reduction of costs for production, performance of works and provision of services of specified quality is determined by the Law of Ukraine on energy saving [1]. The oil, gas and oil refining industry of Ukraine is one of the strategic sectors of the economy, which provides the needs of industrial enterprises, housing and motor transport complex. Metrological support of oil and gas wells for the assessment of their technical condition is carried out using the deep recording manometers. The pressure and temperature of the well are one of the main parameters that are used both to establish the working regime of the formation and the well, and to select the type and regime of the oilfield equipment.