ILKHOM MAKHSUMOV - Academia.edu (original) (raw)

Papers by ILKHOM MAKHSUMOV

Электричество, Nov 27, 2023

The article addresses mathematical description of a following cascade control system with a feed ... more The article addresses mathematical description of a following cascade control system with a feed drive. A neural regulator is developed in Matlab-Simulink. This research compares application possibilities of a neural network regulator and an ordinary P-regulator. It also addresses the design process of a neural controller based on existing traditional regulators. During synthesis procedure, the neural regulator for stabilizing the speed of linear motion and compensation vibration occurring in the elastic elements of lathe machine’s feed drive is proposed. In this article several algorithms as Moller, Levenberg-Marquardt, Shelb-Ribira, gradient descent for training the neural regulator are compared. Comparative studies of several learning algorithms for creating neural controllers are provided.

Резюме. Цель-провести анализ производительности солнечных модулей в зависимости от климатических ... more Резюме. Цель-провести анализ производительности солнечных модулей в зависимости от климатических характеристик местности, химических и электрофизических свойств пыли; исследовать влияние загрязнения п оверхности фотоэлектрических модулей на генерацию электрической энергии и определить срок покрытия п оверхностей пылью до критического значения по снижению выработки энергии. Эксперимент проводился в апреле 2022 года в двух регионах: Республике Таджикистан и Челябинской области Российской Федерации. При иссл едованиях были проанализированы работы ученых разных стран по влиянию загрязнения на генерацию модулей, проведены сравнительные натурные эксперименты по производительности солнечных модулей и их корреляция с метеорологическими данными регионов. Установлено, что концентрация пыли в Челябинской области соста вляет 12-19 мг/м 3 , что значительно меньше, чем в Таджикистане, но из-за мелкодисперсной структуры ее сложнее удалять с поверхности. Результаты экспериментов показали, что в Республике Таджикистан мощность запыле нного модуля за первую декаду апреля (начало пылевых бурь) снизилась на 46,64% относительно заявленной производителем номинальной мощности солнечного модуля. Для условий г. Челябинск-крупного промышленного центра-выработка электроэнергии модулями за этот же период снизилась в среднем на 7,1%. Это свидетельствует об актуальности проблемы защиты фотоэлектрических модулей, которую необходимо решать для поддержания генерации электроэнергии в номинальных режимах в данном регионе. Установлено, что периоди чность очистки для сохранения параметров модулей без специальных устройств защиты от загрязнений должна быть в среднем не реже одного раза в неделю для обоих регионов. Предложено устройство, предотвращающее запыление поверхности модулей на основе электронно-ионной технологии и использование голографической пленки, защищающей модули не только от пылевых загрязнений, но и от действия инфракрасных лучей. Данные устройства являются предметом дальнейших работ по их усовершенствованию.

The article substantiates the need to protect the surface of solar modules from overheating, sinc... more The article substantiates the need to protect the surface of solar modules from overheating, since with an increase in their temperature, the generation of electrical energy decreases, and with prolonged exposure to high temperatures, for example, when operating in hot climates, it can lead to a rapid failure of installations due to their degradation. It is proposed to use a holographic film to protect solar modules from overheating, the internal structure of which is made in the form of prismatic concentrators of solar rays – prismacons. Such a holographic pattern of the film increases the concentration of sunlight in the visible part of the spectrum, thereby increasing the efficiency of the modules. The main geometrical parameters of prismacons were calculated, the optimal angle of internal reflection and concentration coefficients were determined. With the help of the MATLAB software package, the simulation of generation by solar modules using the proposed protective film was carried out, which confirmed the calculations and showed the feasibility of using holographic thermal protection at both individual and industrial solar energy facilities.

Vestnik Permskogo nacionalʹnogo issledovatelʹskogo politehničeskogo universiteta, Aug 13, 2020

The reduction of the life of solar modules during their operation occurs for various reasons, one... more The reduction of the life of solar modules during their operation occurs for various reasons, one of which is their degradation due to overheating of surfaces in operating conditions at elevated air temperatures. The standard current-voltage and power characteristics of solar modules, indicated by the manufacturer, determine the values of the main energy parameters and do not always correspond to the external conditions where this solar power plant works. In this regard, it is necessary to know how much the generation of electricity will change under real operating conditions. Purpose of research: to develop a structural scheme for calculating the energy characteristics of solar modules, taking into account external parameters that affect their effective operation. Results: to solve this goal, the basic parameters of the solar module and the environment were investigated. It has been established that the temperature coefficient of power depends on environmental conditions, the type and quality of the material of the solar modules and determines the degree of their degradation, and the correct choice of the installation location of the modules ensures the reliability and durability of their work. The volt-ampere and power characteristics of the solar module were built with a change in temperature, and they were compared with the standard characteristics of the manufacturer. It is proposed to maintain the efficiency of the solar module near the point of maximum power to use a special holographic film with the functions of protecting the surface from infrared radiation. Introduction to the structural scheme of calculating the energy parameters of the solar module of the thermal protection element will allow you to adjust the energy characteristics of the modules. Practical relevance: a compiled block diagram of calculating the energy characteristics of solar modules in real operating conditions allows you to take into account all the parameters that affect the operational parameters of the modules and determine the most optimal conditions for their operation for maximum power generation.

The article outlines the problems of reducing the efficiency of solar modules and their degradati... more The article outlines the problems of reducing the efficiency of solar modules and their degradation due to overheating of surfaces in working conditions at elevated temperatures. It is shown that the temperature coefficient of power depends on environmental conditions, the type and material of solar cells and their quality and determines the degree of degradation of solar modules. Options for improving the reliability and durability of solar modules due to the correct choice of module installation locations, the use of high-quality modules and films protecting devices from mechanical damage and pollution are given. Based on the solar cell equivalent circuit, the basic energy parameters of the solar module are calculated. It was found that the short circuit current is practically independent of the ambient temperature and the surface heating of the module. The output power of the solar module is proportional to the voltage, which largely depends on the heating temperature of each solar cell. To maintain the efficiency of the solar module near the point of maximum power, it is necessary to provide thermal protection of the surface from the influence of high temperatures. A structural calculation scheme has been drawn up taking into account external parameters that affect the operational parameters of the modules, in which thermal protection of its surface is an important element in calculating the energy characteristics of solar modules.

E3S web of conferences, 2019

This paper explores the problem of overheating of solar modules as a result of exposure to sunlig... more This paper explores the problem of overheating of solar modules as a result of exposure to sunlight. An increase in temperature above the standard leads to the degradation of solar modules and their premature decommissioning. Cooling the working surface is a key factor that must be considered in order to achieve higher efficiency in the operation of solar photovoltaic systems. Based on the considered methods of cooling and removing excess heat from the surfaces of the modules, an inexpensive and technologically advanced method for protecting solar modules from overheating using holographic films was proposed. The article presents the results of comparative laboratory tests of solar modules using such a holographic thermal protection. It is shown that when using a film, the SM performance does not change, and in some cases even gets better. The surface temperature of the module depends on the angle of its inclination to the horizon, which must be taken into account when choosing the location of installation of solar power plants. The experiments confirmed the assumption of effective protection of the modules from overheating using holographic thermal protection and showed its promise.

MATEC web of conferences, 2018

This study examines the results of thermal tests on a 6(10) kV digital combined current and volta... more This study examines the results of thermal tests on a 6(10) kV digital combined current and voltage transformer conducted in an environmental chamber. This measuring instrument consists of current and voltage transformers, featuring a resistive divider, and is used for commercial and technical electric power accounting. Ambient temperatures and levels of insolation on the transformer surface were set for the environmental chamber, with simulation of voltage transformer functioning in normal and emergency modes. We determined the time needed for the thermodynamic system to move to steady heat exchange mode, and also the final temperatures in the lower resistors and on the surface of the voltage transformer insulation cover. The results of our study have been used in developing algorithms for self-diagnostics of the thermal state of a digital combined transformer.

Èlektrotehničeskie i informacionnye kompleksy i sistemy, 2019

The article provides an analysis of methods for determining the solar modules surface temperature... more The article provides an analysis of methods for determining the solar modules surface temperature to monitor its condition, overheating and detecting malfunctions, identifies an infrared image visualization method as the most effective for conducting experimental studies, and shows its advantages compared to other methods considered. Experimental studies to determine the solar modules temperature, the results of which are presented in the article, were carried out in the Republic of Tajikistan, which is characterized by high summer air temperatures and, accordingly, the reliability of the modules is seriously raised. It is shown that modules overheating is accompanied by their rapid degradation and a decrease in power generation. To determine the heating temperature on the solar module front and rear surfaces, the infrared imaging method using an infrared ScanTemp 490 type thermometer was used. To reduce the heating, it was proposed to use a holographic film glued to the entire sensing surface of the module. The parameters taken during the experiment were compared in terms of the two modules efficiency: with a film deposited on the module entire surface and without a film. The study results showed that the module heating temperature when using the film decreases, while the module generated power becomes higher. It was found that the temperature of the module surface heating and power generation depends on the ambient temperature and on air humidity during the day. The actual values of current, voltage and power for two experimental modules were determined. It was established that the change in the values of current and voltage obeys the law of the arrival of solar radiation on the surface of the receiving site, while the current and voltage on the module with the film are higher than on the module with the open surface. The results obtained allow us to conclude that the proposed method for reducing the overheating of modules can have a significant effect when used on a larger number of modules, for example, solar power plants.

2019 International Conference on Electrotechnical Complexes and Systems (ICOECS)

This article provides a calculation of the gross technical and economic potential of solar energy... more This article provides a calculation of the gross technical and economic potential of solar energy from the Penjikent district in order to determine the possibility of using it to obtain and provide electrical and thermal energy. The results of the calculation of solar energy resources for the Penjikent district of the Republic of Tajikistan, obtained on the basis of using NASA metrological data for the last 20 years, are presented. Using data from NASA and the RETScreen Expert computer program, the work also determined the average monthly solar radiation intake for 22 years for all cities of Tajikistan and is given in the table. The conclusion was made about the expediency of using solar photovoltaic modules in the territory of the Penjikent district, where there is still no electricity in most areas of this region.

2020 Russian Workshop on Power Engineering and Automation of Metallurgy Industry: Research & Practice (PEAMI)

Case Studies in Thermal Engineering, 2022

2020 International Conference on Industrial Engineering, Applications and Manufacturing (ICIEAM), 2020

ELECTRICAL AND DATA PROCESSING FACILITIES AND SYSTEMS, 2019

E3S Web of Conferences, 2019

MATEC Web of Conferences, 2018

Bulletin of Perm National Research Polytechnic University. Electrotechnics, informational technologies, control systems, 2020