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Purpose. The article is devoted to the creation of traction motor protection by modern methods and means based on a programmable logic controller (PLC). Methodology. To simulate motor fault monitoring in laboratory conditions, magnetic field and temperature sensors were installed on a small powerful induction motor, and then the data obtained from the sensors in normal and overloaded motor modes were analyzed. Based on the research, protection methods were developed. Findings. Previously used simple motor protection systems based on components such as timers, contactors, electromagnetic switches, voltage and current transformers were slow and inaccurate, and had low sensitivity. However, the production of PLCs and their application in this industry has eliminated these problems. The intensive operation of motors as the main executive equipment requires the creation of modern automated protection systems to ensure their reliable and stable operation. Originality. The paper improves the method of protection of traction motors based on the use of programmable logic controllers. In addition to the voltage and current parameters, the proposed method involves monitoring the magnetic field. It also provides for the possibility of adjusting the protection response time. As a result, in the event of overload, short circuit, and other non-standard situations, the improved method provides the system with the ability to make more accurate and reliable decisions. Practical value. The TIA Portal software package has modeled a traction motor protection system by temperature and current and considered its practical application. To make such systems more effective, in the future, comprehensive protection systems based on the diagnostic state of the traction motor can be developed. In addition, an effective system can be created by providing SCADA control of the engines of several vehicles simultaneously.

Traditional approaches to automatic control occupy a major role in today's industry and will probably continue to be mainstream for many years to come. Control systems using elements of modern intelligent control technologies are becoming increasingly popular in current conditions. In the field of public catering, workers will be able to perform the functions of a waiter, bartender, cashier, cleaner and others. The automation of the dosing of liquid products is relevant, in particular, ensuring the appropriate temperature regime when dosing beer at catering enterprises using elements of intelligent control technologies. In none of the research results published in the open access, the issue of ensuring accurate maintenance of the regulation temperature of beer during its dosing has not been resolved. At the Department of Automation of Technological Processes and Robotic Systems of the Odessa National University of Technology, as part of the research work of a master's student, a scientific study of the process of dispensing beer as a control object was carried out and a automatic control system (ACS) of the temperature regime during its dispensing based on elements of intelligent control systems was proposed. A comparative analysis of the functioning of the classical ACS and systems using fuzzy and neuroregulators showed the advantages of their use over the classical one for controlling objects with non-linear characteristics. For technical systems with a random nature of disturbances, their high-order dynamic model and with a nonlinear characteristic, we can talk about the problem of control under conditions of uncertainty. The use of fuzzy and neuroregulators provides roughness and stable convergence of transient processes in a system, so this approach should be considered appropriate. [ABSTRACT FROM AUTHOR]

The paper aims to develop a new method of designing one-dimensional automatic control systems with P, PI, and PID control laws. The method scope is static and astatic plants, and it aims to minimize the influence of measurement noise on the dynamic properties of the control system. Achievement of this aim should be without complicating the structure of the control channel. The scope of the method is the problems of stabilization of relatively fast processes, which most of the time are controlled by regulators in the mode when the control error is close to the measurement error. Examples of such problems are: temperature stabilization in a heat exchanger or flow (pressure) control. The goal is achieved by solving the following tasks: 1) to develop rules for PID-type controllers for static and astatic control plants with a dead tune, which achieve a guaranteed value of the ratio of the output dispersion to the input (according to the white noise model); 2) to investigate the rules on the model of the technological plant, which takes into account the peculiarities of the automation in the control channel. The most significant result of the work is a method that represents a set of simple rules similar to the rules of other known methods of tuning PID-type controllers. A plant's reference dynamic mode is supposed in the form of a combination of a first-order aperiodic or integrating link with a dead time link. The method is also suitable for hard-controlled plants with a significant or dominant dead time. An example of the application of the developed method for controlling the temperature in the heat exchanger of a beer distillation column using a PI controller is demonstrated. It is shown that the method allows a reduction of the dispersion by a quarter compared to the controller obtained using the pidtune program. Similar results are achieved for other PID-type controllers. [ABSTRACT FROM AUTHOR]

The materials of this article contain a concise and systematic presentation of a new theoretical and experimental approach in the development and generalization of methods for laser polarization introscopy of polycrystalline architectonics of phase-inhomogeneous layers with various mechanisms of optical anisotropy — linear and circular birefringence and dichroism. The main task of the work was the development of an analytical polarization Mueller-matrix approach, which provides the possibility of differentiating the optically anisotropic properties of polymeric materials with diffuse light scattering. The implementation of this problem was based on the theoretical formalism of the decomposition of the Mueller polarization matrix in the basis of differential matrices of the 1st and 2nd orders. The 1st order differential matrix operator characterizes the coordinate distributions of the mean values of the linear and circular birefringence and dichroism parameters. The 2nd order differential matrix operator determines the fluctuations in the parameters of the phase and amplitude anisotropy of the polycrystalline architectonics of polymeric materials. This work is aimed at generalizing the methods of laser polarimetry to the case of partially depolarizing optically anisotropic polymer layers. Mueller’s differential matrix mapping method was proposed and substantiated for reproducing the distributions of the parameters of linear and circular birefringence and dichroism of methyl acrylate layers under different temperature conditions (200 — group 1) and (450 — group 2). For an objective analysis of the obtained experimental data, we used a statistical approach, which is based on the calculation of a set of central statistical moments of the 1st–4th orders, which characterize the specifics of the coordinate distributions of differential Mueller-matrix maps of methyl acrylate layers under various temperature conditions (200 — group 1) and (450 — group 2). On this basis, the most sensitive statistical criteria for the temperature control of these samples were determined.

The effect of thermal action in the process of electrodynamic treatment (EDT) of welded joints of AMg6 alloy on their stressstrained states was investigated. Based on the of the Prandtl-Reuss ratio for the movement of elastic-plastic environment at elevated temperatures, a mathematical model of evaluation of stress state of metal materials was developed as a result of their interaction with the electrode-identer at EDT. On the basis of the developed model, a calculated evaluation of the effect of elevated temperatures on residual stresses of a preliminary strained plate of AMg6 alloy as a result of EDT was carried out. The verification of the results of the calculation with the use of welded plates of AMg6 alloy of 2 mm thickness was carried out. Thermal action was carried out with the help of the accompanying EDT preheating of the weld metal. To evaluate the effect of the thermal potential of EDT on residual stresses, TIG welding of butt-joint specimens was performed. EDT of specimens at the temperature TEDT = 20 and 100 °C was performed. Applying the method of electron speckle-interferometry, the values of the longitudinal component (along the longitudinal axis of the weld) of residual welding stresses in the central cross-section of the specimens before and after EDT were measured. Thermal impact on EDT was provided with the use of a heat gun, and the heating temperature was controlled by an infrared thermometer. It was revealed that heating of the weld in the process of its EDT along the longitudinal axis of a butt joint provides greater values of residual compression stresses in the centre of the weld as compared to the treatment at T = 20 °C. [ABSTRACT FROM AUTHOR]

Purpose. Based on the research work of units and parts of rolling stock undercarriage in transient modes of emergency situations it is proposed to optimize the sequential placing of peripheral contactless devices for technical control of locomotives and cars on railway lines. Methodology. Investigation of transient processes of temperature increase of faulty axle bearings of locomotives and cars during remote technical diagnosing allows one to organize theory and hardware construction of the peripheral systems for testing the rolling stock on the move. Automatic control of the technical state of the rolling stock on the move – the last and in some cases the only possible process step, which allows revealing unacceptable defects in rolling units and thereby prevent emergencies in railway transport. Findings. Based on the research it was proposed a solution to the optimization problem of placing peripheral control devices of rolling stock when moving according to the criteria of the linear and exponential nature of heating defective axle boxes of wheelsets and other units of undercarriage. The risks of train stop on the railway line because of the erroneous classification of normally heated axle boxes as overheated, as well as the consequences of classification of overheated axle box as normally heated axle boxes were evaluated. Originality. Optimization model of placing peripheral control devices based on probabilistic criteria for evaluating the degree of permissible risk that, at a minimum, should not be exceeded during the transition to control technical means. A functional block diagram of test hardware diagnostics for the wheelsets when determining the gradations of digital indicators of defects was proposed. Practical value. The value of the results obtained lies in the improvement of a method of placing technical control peripheral devices and diagnosing rolling stock when determining the distance between the control stations in the same direction and organizing tracking modes for railcars with developing defects. From a technical point, reduced error probability is directly related to traffic safety and diagnostic algorithms.

In the development of centralized temperature control systems with analog bus, the issues of error reduction are investigated. The main errors of such a system are the quantization error and the error due to noise. Based on the analysis of devices, design schemes and methods for noise immunity, it was recommended: to reduce the error due to noise by introducing a phaselocked loop (PLL) system that regulates the phase of the proposed controlled generator so that it corresponds to the reference signal phase or differed from the function known over time. A comparative analysis of existing methods has shown that the most effective method of measuring frequency is the "method of dependent measurements", which takes the best of the previous two and is accurate, fast and noise-proof. For warehouses of multi-temperature type of class "C" the automatic control system of temperature of the centralized type on the analog bus which has high technical characteristics is offered, namely: speed - time of standing on a point less than 0.1 seconds; the system multiplicative error does not exceed 0.15%, and the additive reduced error is equal to 0.05%; noise immunity is reduced from 30% error to almost zero. The system consists of N identical modules of signal input of sensors of non-electric quantities - resistive R1 (or capacitive C1), which are included in the frequency-forming units of PWM modulators. 8 sensors are connected to each of the modules. One of the sensors in the next module is selected using the DaisyChained serial control bus or the serial SPI peripheral interface. The use of such systems is cost-effective and allows for small premises to significantly expand the market for warehousing products. [ABSTRACT FROM AUTHOR]

The article considers the application of modern methods of setting up double-loop feedback control system with the introduction of a differentiator at an intermediate point (DACS). The purpose of the article is to analyze the existing methods of setting up the DACS, to study the modern methods of setting up on the example of a thermal power plant, as well as to compare it with the classical method. On the basis of the conducted analysis for tuning of system of regulation of a temperature mode of the direct-flow boiler unit the technique offered by V. Sviridenko is chosen. The procedure of identification of control loops is carried out. Models of temperature contours of the water-steam path of the direct-flow coalfired boiler unit are obtained, the transient characteristics of the inertial and intermediate sections are given. DACS was calculated according to the classical method, and a single-circuit control system was calculated for comparison. The results of computer simulation of the temperature control system of the water and steam tract show that the classical method of tune the differentiator does not provide the required quality of transients, there is a large fluctuation, which is unacceptable for this heat plant. For the same plant, the calculation was performed according to the method of V. Svyridenko. The obtained transients have a greater degree of attenuation by an average of 30%. According to the results of the study, it can be concluded that the proposed method of setting the DACS in comparison with the classical method is better suited for setting up plants, which include direct-flow boilers. The considered technique is relatively simple from the point of view of its use, has clearly formulated criteria and is supported by a full set of calculation formulas. The shortcomings of this technique are identified and recommendations for its further improvement are given. [ABSTRACT FROM AUTHOR]

Copyright of Science-Based Technologies is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose. The aim of the work is to improve the work of hair styling devices, which is aimed at increasing the efficiency of hair styling under the action of sufficiently high temperatures with the least damage to it. To achieve this goal, the following tasks were solved: the relationship between the physical properties of hair and temperature regimes of curling was analyzed; experimentally investigated the distribution of curling temperature during heating and cooling; the distribution of the temperature of the curling iron when heated with dry hair and with moist hair was experimentally studied. Methodology. The methods of mathematical modeling, methods of mathematical physics, methods of experimental researches with processing of results of experiment by means of a modern software product and computer equipment are used in the work. Findings. Analytical and experimental studies have shown the need for a uniform temperature field on the surface of the work surface to achieve the desired result. The necessity of temperature regulation in devices for work with hair is proven. Originality. The possibility of using the installation for experimental evaluation of temperature control in devices for working with hair is substantiated, which will significantly increase the time of continuous operation of the device and reduce electricity consumption. Practical value. A stand for research and analysis of different temperature regimes of electrical appliances has been developed. The thermostat circuit for temperature control in devices for work with hair is applied. It has been proven that you need to choose the temperature in relation to the condition and type of hair, so as not to cause great harm. Due to its small size, economic and technical indicators, this stand is easy to use when studying the temperature conditions in devices for working with hair in the work space, which contributes to more modern and demonstrative training. It is proposed to use the two-position law of temperature regulation for the surfaces of the working bodies. [ABSTRACT FROM AUTHOR]

Purpose. Determining the rational structure of the automatic control system of the motorcompressor, which provides minimal energy losses when switching on and going to a steady state mode of operation of a household refrigerator. Methodology. The methods of simulation modeling, comparative analysis, research of control systems and the main provisions of technical thermodynamics and the theory of automatic control are used in the work. Findings. The paper considers the principle of operation of the refrigeration unit of a household refrigerator, schematically shows its main elements and the relationship with the steam compression cycle. Simulation models of automatic control systems based on proportional-integral-differential controller, fuzzy and hybrid controllers have been developed. The proposed models allow to evaluate the quality of temperature control in the refrigeration compartment and to determine energy losses during transients. The results of computer simulation of transients in temperature control systems due to changes in the performance of the motor-compressor and the obtained values of power losses are presented. It is established that the smallest losses of the electric power at instant increase of heat inflows in refrigerating department occur at application of a fuzzy regulator. It is determined that the use of fuzzy controllers in automatic control systems reduces the duration of transients, the time of the first negotiation, the number of oscillations, but leads to static error and increases the maximum deviation from the set temperature in the refrigerator compartment. Originality. Simulation models of control systems of the motor-compressor of a household refrigerator for assessment of quality of regulation and definition of losses of the electric power during transient processes are developed. Practical value. The ways to increase the energy efficiency of household refrigerators through the introduction of control systems with fuzzy regulators are proposed. [ABSTRACT FROM AUTHOR]

The article solves the problem of recognizing the shape of products produced by a new complex of equipment for the production of dumplings of special, cubic shape. The production of complex difficult-to-sell products is used to increase the economic component and eliminate counterfeiting. When manufacturing goods, there are a number of difficulties that need to be overcome. One of them is a minced-temperature fork in the dough that has room temperature. Having conducted a series of active experiments with frozen minced meat and warm dough, having received and processed the obtained results, we came to the conclusion that the created equipment should have not only an automatic control system, which includes the ability to control the complex, but also contain algorithms that will allow to calculate mathematical models necessary to maintain the properties of the test temperature. And also to include in the complex capabilities of computer processing of received products and using modern communication technologies, to ensure the transfer of information that will be available for remote work of the complex itself, as well as information about its products. Using a new, hard-to-realize shape and modern technologies, the complex will in the future not only produce new products with a form of tamper-proof, but also reduce production costs. Efficiency will also be conditioned by the fact that for the products of this form, the price may be increased considering the content of the best ingredients and the possibility of using a more compact packaging. Since packs of cubic semi-finished products will actually have no free space, unlike modern packs of ravioli products containing up to 20% air. This will also increase efficiency when storing and moving products. It is also worth noting that this equipment will be able to produce new products of semi-finished products, which include not only currently used common ingredients such as pork and beef, but also poultry, fish and many different recipes minced meat and dough. Which, in turn, will expand the range of products manufactured semi-finished products. The final stage of dumpling preparation is to check and reject it. If the dumpling shape meets the regulations, it is sent for further freezing; otherwise, it is sent for processing, with adjustment to the heating temperature control system. Modern computer methods allow you to retrieve this data from a photo. There are 3 photo processing methods to identify the required properties: static methods, sample comparison methods, neural networks. The paper examines ravioli recognition using the OpenCV open access library, which already has many recognition features and is constantly being updated with new ones. [ABSTRACT FROM AUTHOR]

Purpose. The aim of the article is to study the influence of the main factors on the hydrogen evolution performance, in particular, the concentration of components, the nature of the electrolyte, the composition and surface condition of the aluminum alloy. Methodology. For research, a MICROmed device was used, which has a temperature control and a mixing function. Weight corrosion tests were evaluated gravimetrically using the brand scales CERTUS Balance CBA-150-0.02. pH of solutions was measured using pH - meters mark 150 MA. Processing of the results was carried out by mathematical planning of experiments using the software package Exel 2016. Results. It proposed a low-temperature chemical synthesis method by reacting hydrogen alloys of aluminum with alkali solutions with additives activators. The basic patterns of change in the dissolution rate of the AK7 alloy and formation of hydrogen halide from the impact of ions in alkaline solutions and its influence on the process condition of the alloy surface and reaction products. In this alloy, the most influential is the admixture of silicon, which is 3-6% by weight. The influence of the kinetic parameters of dissolution of the AK7 aluminum alloy on the synthesis of hydrogen as a source of environmentally safe thermal energy is determined. Scientific novelty. The dependences of the process of hydrogen evolution in alkaline solutions by the mechanism of hydrogen depolarization on the nature of the aluminum alloy and impurities of activators in the electrolyte are established. Practical value. The processes of the metal chemical cycle of hydrogen production have been studied; they create the conditions for the further development of the technological process of aluminodepolarization synthesis of hydrogen without the use of membrane electrolyzers. This method is important for the needs of small energy in small quantities. [ABSTRACT FROM AUTHOR]

The issue of food quality is given an unconditional priority, as evidenced by the introduction of new food legislation in in Ukraine. When implementing the “from field to fork” principle, each participant in the long chain of production must provide the necessary conditions for obtaining quality and, above all, safe food. The nutritional value of products made from grain raw materials is determined by the quality indicators of grain. In order to ensure safe production, food market operators, including primary producers, are required to develop and implement ongoing procedures based on HACCP principles. Among the tasks of technological expertise is the analysis of the level of safety of production and finished products. Therefore, technological examination of post-harvest processing and storage of wheat grain and its compliance with the HACCP principles are the tasks of ensuring the highest quality of grain raw materials. When implementing HACCP principles at any production site, including in the grain industry, the safety measures taken must meet the risks of product contamination. The goal of the paper is to determine the most important factors that affect the quality of wheat grain during post-harvest processing and storage, as well as stages of the technological process critical to the safety of grain. Risks that threaten contamination of raw materials can occur at different stages of the elevator operation and are divided into physical, chemical, and biological. The analysis of each stage of post-harvest processing and storage of wheat grains, indicating the appropriate hazardous factor with an assessment of the likelihood of manifestation and severity of risk. Based on the analysis, the stages of the technological process are identified, which give rise to the most dangerous factors with the necessity of obligatory control over the parameters of contamination: biological factor at the stages of reception, chemical factor at drying and long-term storage. Physical and chemical factors occur at the stages of acceptance and purification, are not so significant, they can be prevented when implementing operational programs, prerequisites. The reasons of dangerous factors occurrence and control measures are indicated to reduce the risk of their occurrence or reduce the negative impact. Based on the analysis of the occurrence of hazardous factors at different stages of the technological process (post-harvest processing and storage of wheat grain), the following parameters are obligatory to be controlled: grain temperature, humidity, pest infestation of grain stocks, organoleptic indicators in accordance with the rules of the current regulatory and technical documentation. [ABSTRACT FROM AUTHOR]

Currently, alternative energy sources are very important for preservation of the environment. In the food industry one of the most common types of storage products is the drying. When using gas and electricity, this process becomes very expensive. We have designed specially driers that work exclusively on solar energy. They used for drying various foods -fruits, vegetables, herbs, berries, mushrooms, etc. For the drying process are used solar thermal air collectors (STAC) which made by us on the basis of our selective absorbent coating. The research of the thermal characteristics of the STAC was carried out on a specially constructed experimental stand. As a result of the tests it was confirmed that the fans of the system can support air supply in the range of 20-120 m3/h. In the summer, at a temperature of 25-350C, the temperature of the flow of air at the outlet from the collector can reach 70-75 °C. For all-time drying there are developed special innovative energy storage batteries at National Technical University of Ukraine "Kyiv Polytechnic Institute". Batteries can be charged from solar panels, have a shorter charging time, the possibility of charge-discharge at low and high temperatures, higher reliability, are safe and durable. At present, for such types of solar dryers we are developing special devices for controlling and regulating the temperature and humidity of drying, which is very important when drying medicinal herbs, cereals, fruits, mushrooms, etc. Indeed, the deviation of a few degrees during the drying of such products can significantly change their consumer characteristics.Our innovative and efficient solar dryers systems provide a very easy installation, with the ability to fit in the garden, on any area or indoors. In this case, a person does not bear any costs and additional charges for maintenance during their operation, as they fully work from the energy of the sun. [ABSTRACT FROM AUTHOR]

The study focuses on the development of microcontroller devices and Internet items in the field of refrigeration technology. The availability of information on the current state of the temperature parameters from the sensors and, if necessary, remotely change the values of these parameters greatly increases the efficiency of control of the technological process in which the refrigerating equipment is involved. The aim of the work is to increase the efficiency of control of temperature and humidity in the room due to the development of a microcontroller remote control device. One of the solved tasks is the development of an implementation algorithm for remote control of temperature parameters for use in a local computer network. An explanation for the implementation of the developed algorithm is formed. Much of the work focuses on the selection of software and hardware that will enable the device to be developed, a detailed analysis of existing options with justification of the choice, the advantages and disadvantages given. Among the criteria for choosing - the cost of the device, the time of development, the complexity of perception, the degree of convenience and simplicity of the programming language, open architecture and software code. Microchip microchip single chip Ethernet chips ENC28J60, ENC424J600 and KSZ8441 have been selected as the main chips for the development of a remote control of temperature and humidity. As a development environment, it is proposed to use the free Arduino programming environment and language (Arduino Duemilanove hardware plus Arduino EthernetSheeld V1.0, as well as the TCP / IP software stack), the WinAVR application development environment. The device is programmed through the USB interface without the use of programmers. Devices based on Arduino receive environmental information (temperature, humidity, etc.) with different sensors, and can control various actuators. The mounted device connects to the LAN, the IP addresses of the device, server and subnet masks are written to the EEPROM microcontroller using the RS232 interface. Also developed is a subroutine that allows you to get data on temperature and humidity of air from the sensor DHT-22, which allows you to calibrate the digital signal on the output. The subroutine runs every two seconds and is used by the application to transfer data through the local network to the computer screen with the help of standard programs Telnet, Putty or others. The analysis of software and hardware enabled us to choose a convenient and free development environment and programming language. Using the results of the analysis will reduce the time expenditures and increase the efficiency of the implementation of the device. The proposed materials are intended to popularize the use of microcontrollers and single-chip Ethernet interfaces for building economic access to local computer networks for the purpose of collecting and transmitting information from sensors of various types, such as temperature, humidity, and others. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Journal of National University of Life & Environmental Sciences of Ukraine. Series: Technique & Energy of APK is the property of National University of Life & Environmental Sciences of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concept of a flexible computerized system of vehicle units thermal analysis and its dynamic characteristics control is offered.

The article is devoted to the issue of the temperature control of a biological object in the magnetotherapy. We develop the mathematical model of the magnetic field influence on a biological object with the control of the temperature variation on the surface epidermis areas. We conduct an experimental research of temperature variation of a biological object with magnetotherapy apparatuses "MIT-11" and "POLUS-4". The quantitative and qualitative estimation of theoretical and experimental research results of a thermal field shows high convergence of results and efficiency of the developed mathematical model of specific thermal action of a magnetic field on a biological tissue. Based on experimental and theoretical research we elaborate the system of temperature control and pointed precisely acting dosage of magnetic field on biological tissue providing high efficiency of the therapeutic effect of required forms of magnetic fields on biological tissue due to the measuring of temperature gradient during the magnetotherapy procedure. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the existing methods of temperature control of the oxygen - converter bath. We investigate the balance method of temperature control, kinetics of burning iron impurities, assimilation of bulk materials, heating of the lining and its relation to changes in the bath temperature. Finally, we present the simulation results of converter melting under the temperature conditions. [ABSTRACT FROM AUTHOR]