The paper presents the developed fiber-optic sensors for monitoring pressure measurement on the elements of mine supports. The sudden destruction of the support leads to the collapse of the mine workings and poses a serious threat to the life and safety of underground workers. A fiber-optic system for monitoring changes in pressures on the elements of mine supports will increase the share of mining automation and reduce the share of manual labor, as well as eliminate measurement errors associated with the human factor. Systematic monitoring of the state of the working elements of the support will allow timely tracking of their deformations caused by an increase in rock pressure on them. Implementation of the system at mining enterprises will expand the use of digital technologies in mining. Timely warning of a mine collapse threat will significantly increase the level of safe mining operations, as well as reduce the cost of supporting mine workings, since elimination of the consequences of destruction is associated with significant material costs. This work presents a developed laboratory testbench that simulates a mine working and elements of an arch support on which are installed the fiber-optic sensors connected to an automated measuring system. The developed hardware and software complex provides the processing of a light spot falling on the surface of a television matrix that is installed at the exit from the optical fiber. The results of visual processing are converted into numerical values, which are used to make a decision about the state of the considered object. In addition to automatic monitoring of the structural integrity condition of the considered object, the system is equipped with a function of a visual display for monitoring results, which makes it possible to track sharp fluctuations and bursts of pressure parameters, based on which the prediction of pre-emergency and emergency situations is performed.

This paper presents the results of complex scientific research aimed at developing a prototype fiber-optic system for controlling the technical condition of buildings, structures, and extended objects. The aim is to develop a quasi-distributed type of fiber-optic control system without electrical signals, with the minimum possible cost of one measurement point. The fiber-optic sensors are based on a new method of controlling the parameters of the light spot by means of a hardware-software complex. The proposed monitoring system is quasi-distributed, is able to determine the damaged and most stressed and deformed areas of load-bearing reinforced concrete structures of buildings at the stage of their occurrence, and will allow for the taking of preventive measures for their protection. The research was carried out on a laboratory bench working together with the hardware-software complex; pixel analysis of changes in the area of the spot and its intensity was used as a fiber-optic sensor. A single-mode optical fiber of the G.652.D 9/125 μm standard was used, with a wavelength of 650 nm. The monitoring system can perform the function of pressure measurement on the building structure, establish the damage zone, and signal in case of an abrupt change in parameters in case of structure destruction. Laboratory tests have shown that the number of channels can be increased to 16 or 32. With the help of this system, it is possible to monitor the technical condition of the underground and above-ground parts of buildings or structures and control their integrity in real-time.

The research addresses the issues of collection and transmission of measurement data when monitoring various construction objects and bridge structures. The issues were resolved by developing a distributed system using Wi-Fi technologies. The results of measurements of the following parameters and data were obtained: the distance between cracks and joints, magnetometer readings and location and possible inclination of objects in three axes according to accelerometer and gyroscope data. By configuring the server, new channels are created for receiving data, which allow their subsequent processing and complete analysis of the study, for example, to solve the problem of predicting the technical conditions of construction and bridge objects. The completeness of the analysis of the study solves the problem of identifying and detecting possible errors and determining delays in the communication system. In general, the validity of all research results plays an important role in predicting the technical conditions of various objects and in finding solutions to problems arising from the technical difficulties of remote control. In this regard, the issue of the validity of the choice of Wi-Fi modules, which take into account the parameters of power consumption and availability of the boards of these modules for programming in order to obtain results of measurements in a long time has been posed and resolved. Setting power consumption parameters made it possible to increase the research time at remote sites, which in turn increases the durability and life of the control system. The simplicity of programming the module boards and support of various electronic sensors allow varying the scope and research objects, thereby expanding the geography of the subject area of research. Therefore, the developed distributed system is easily adapted to the necessary problem areas of research, the monitoring results of which can be used in many areas, such as agriculture, ecology, power, health care, meteorology and others

The paper describes the types of multilevel pulse-width modulation, as well as methods for obtaining control signals for the inverter power switches for each of the types. The dependence of the harmonic composition of the output voltage of the inverter on the number of levels and the switching frequency of the keys of each level is analyzed. By modeling, the dependences of the transistor junction temperature on the number of voltage levels, switching frequency and load power are determined. The power switching system of an inverter with phase-shifted pulse-width modulation in high-frequency mode is analyzed, the dependence of switching losses on inductance is investigated. The ways of solving or improving the control systems of the conductivity losses of the converter flowing through the primary winding of a high-frequency transformer during the free-running period are formulated. The importance of this direction for the technological development of the economy, where efficiency improvements can lower individual utility bills, create jobs, and help stabilize electricity prices and volatility is shown. The most important stage of inverter design is called structural synthesis stage – the choice of topology and modulation algorithm that will ensure the greatest efficiency of the device. In addition, since the efficiency and reliability of inverters depend on the efficiency and reliability of secondary electricity consumers, the task of optimizing inverter circuits is a cornerstone for the effective development of technology and economy. The maximum dynamic power loss at a PWM frequency of 1 kHz reaches only 80 watts compared to the static power loss value of 800 watts

This paper reports a study into designing an information-measuring system that could be used in coal mines that are dangerous in terms of the explosion of coal dust and methane gas. The results of reviewing technical advancements in the field of fiber-optic system development are given. To solve the set task, prototypes of a fiber-optic sensor of a new type and a hardware-software complex were constructed. The research aims to improve the safety of workers at coal enterprises. The result of the theoretical research has established that additional losses related to a micro bending should be taken into consideration while accounting for the effect of photoelasticity. The fundamental difference between the idea reported here and existing analogs is the development of a hardware-software complex capable of working with a single-mode optical fiber of great length with a significant noise level. The data processing unit is equipped with a television matrix and can analyze changes in the pixels of a light spot. The proposed system is quasi-distributed; it controls individual points within a rock massif. The designed hardware-software system provides high noise immunity of measuring channels when the external temperature changes. The research results helped develop an information-measuring system for monitoring the deformation and displacement of rock massif layers based on fiber-optic sensors, capable of operating in an explosive environment. The system makes it possible to control several layers located in the roof of the workings, while the fiber-optic sensor may contain two or three sensitive elements that are connected to different channels. With a sharp fluctuation in pressure and an increase in the displacement parameter, the system triggers a warning signal about the danger.

THE PURPOSE. Conducting a comparative analysis of the problems of efficient power supply torural consumers. Offering solution stop roblems by using multi-fuelmicrothermal power plants based on the Stirlingengine for ruralareas. Justification and description of prospects for the use of multi-fuelmicro-thermal power plants based on the Stirlingengine for ruralareas. METHODS. Methods of computer simulation of thermodynamic processes of multi fuel micro-thermal power plants based on an engine based on an engine with external heat supply are used. A computer simulation method has been developed that allows constructing a PV diagram and processes of changes in the pressure and volume of the working fluid depending on the position of the working piston and the displacer. Mathematical methods of analysis and description of the thermodynamic cycle of an engine with external heat supply are used. RESULTS. Выполнен анализ достижений и уровня современных достижений в области микро электростанций. Установлено направление развития научных исследований по разработке двигателя с внешним подводом тепла. Приведены некоторые результаты исследований по эффективности работы двигателя с внешним подводом теплоты. CONCLUSIONS . Одним из решений проблемы эффективного электроснабжения сельских потребителей может быть внедрения микро тепловых электростанций. Их использование позволит снизить стоимость электроэнергии и обеспечить ее бесперебойную поставку. Основой микро тепловой электростанции является двигатель с внешним подводом теплоты, работающий по принципу Стирлинга.