Автоматизована система керування установкою комплексної підготовки газу до транспортування

Abstract

The dissertation for the degree of candidate of technical sciences in specialty 05.13.07 – Automation of control processes. – The National Technical University «Kharkiv Polytechnic Institute», Kharkiv, 2021. The thesis is dedicated to the solution of the scientific and practical issue of increasing the efficiency of the moisture separation process from compressed gas stream by reducing the time and fluctuations of transient processes under the conditions of transient disturbance parameters of the gas stream. The research methods are based on modelling gas flow processes in the object of control, which is based on the laws of gas dynamics and thermodynamics, followed by the use of methods of integral and differential calculus, in particular the finite element method. The study of the dynamics of the mechatronic device involved in the system is carried out on the basis of the laws of electrical engineering and mechanics. Linearization of the control object is performed on the basis of Jacobian matrix calculus. Controls are based on the methods of automatic control theory and matrix calculus theory. The principles of extreme regulation are used to optimize the modes of moisture separation. The presence of delays in the reaction time of the object to the control effects of the regulator leads to the use of subordinate and adaptive control of the cooling and moisture separation processes that accompany the preparation of gas for treatment. A two-tier structure has been chosen to build the control system, which provides communication between the peripheral equipment and the workplace of the unit operator. On the basis of the developed models of gas treatment preparation processes, the identification of parameters of moisture separation experimental unit from the air flow has been carried out and the methods of synthesis of regulators of gas treatment preparation process have been worked out. The use of object modelling automation tools in MATLAB environment has made it possible to obtain a multipoint linearized object model. According to the control criterion, which is formulated as "maximization of dried gas consumption with minimal deviation from the dew point temperature", a two-circuit regulator of the moisture separation process is built. The inner circuit is created using an adaptive pressure regulator according to the tabular control method. The settings of the adaptive regulator are adjusted depending on changes in the parameters of the gas flow entering the throttling. The outer circuit is created by introducing extreme control by the step method, which maximizes the stream of dried gas and the stability of the parameters during the control process. The electric position of the latch, which determines the cross-sectional area of the throttle, i.e. the throttling mode, is built on the basis of a stepper motor. As a result of structural-parametric synthesis of unit regulators, relay regulators of processes of additional stream cooling and phase equilibrium maintenance by regulation of condensate level have been implemented. In order to implement the results of research in industry, a SCADA system of moisture separation experimental unit has been developed and a mnemonic scheme of control of the separation process has been implemented.