ISSN 2223-0858 (Online) Subject: theoretical and applied sciences, technology and industry in the field of energy and automation Year established: 2009 Founder and publisher: National University of Life and Environmental Sciences of Ukraine Publisher registration number (EDRPOU): 00493706 Publisher's ROR: https://ror.org/0441cbj57 DOI prefix: 10.31548 Published 6 time a year Media identifier R40-02287. The National Council of Television and Radio Broadcasting of Ukraine Decision No. 1796 of 21 December 2023, protocol No. 31 Speciality DAK: Technical Sciences Scientific journal cluster: Safe, clean energy and energy efficiency. Subject areas in which the journal publishes scientific papers: G3 electrical engineering; G11 - mechanical engineering, G4 energy production. Languages of the publication: Ukrainian, English Address: Heroiv Oborony st., 12, Kyiv-03041, Ukraine Phone: +38 044 527 85 22
Національний університет біоресурсів і природокористування України
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The use of biomass as a factor for increasing the energy-ecological efficiency of boiler plants and ensuring energy sustainability in conditions of martial law
The disruption of energy infrastructure functioning in Ukraine under martial law exacerbates the problem of ensuring reliable heat supply. The dependence of boiler plants on natural gas reduces their resilience to crisis impacts, highlighting the need to transition to alternative and locally available energy sources, particularly biomass. The aim of this article is to assess the potential of using biomass to enhance the energy and environmental efficiency of boiler plants and ensure their energy resilience. To achieve this goal, the study focuses on identifying key characteristics of biofuels, evaluating their impact on boiler performance, and substantiating the feasibility of implementing bioenergy solutions based on international experience. The study employs a comparative analysis of the characteristics of natural gas and various types of biomasses, a systems approach to considering boiler plants as integrated energy-technological systems, calculation methods for assessing thermal and economic performance indicators, as well as elements of experimental analysis of fuel composition and generalization of foreign experience. It has been established that using biomass contributes to increasing the energy autonomy of boiler plants and reducing the cost of heat production compared to natural gas. The efficiency of biofuel boiler operations depends on the consistency of their technological components and the consideration of fuel properties. The feasibility of using wood pellets and torrefied biomass for medium-capacity boiler plants is substantiated, while agro-biomass requires accounting for corrosion and slagging risks. The adaptation of European bioenergy models to domestic conditions is demonstrated. The use of biomass is an effective approach to improving the energy-environmental efficiency and resilience of heat supply systems under martial law. Transitioning to biofuels ensures diversification of energy sources, reduces dependence on imported resources, and promotes the development of local fuel markets. Implementing this approach requires a comprehensive consideration of technical, economic, and resource factors. Recieved 2025-11-21 Recieved 2026-01-21 Accepted 2026-02-11
Copyright (c) 2026 Energy and Automation https://creativecommons.org/licenses/by-nc/4.0
Mathematical modeling of dynamic characteristics of rotary-blades wind power installations under stochastic wind loading conditions
The integration of rotary-blades wind power installations into modern energy systems is becoming increasingly important due to the rapid growth of the share of renewable energy sources. At the same time, the operation of wind power installations is significantly different from traditional sources of generation, as their performance directly depends on the speed and direction of the wind, which are random in nature. This leads to significant fluctuations in the mechanical and electrical parameters of the system, complicates the process of regulating the frequency and active power of the generator, and creates increased requirements for the stability of the power system as a whole. The purpose of the study is to develop a mathematical model of a rotary-blade wind power installation taking into account stochastic wind load for analyzing the dynamics of the installation and tuning the wind generator frequency control algorithms. Mathematical modeling is based on equations of rotational motion of the rotor and wind wheel, described through torque and moment of resistance forces, as well as on equations of air flow motion, taking into account turbulence and random changes in speed and direction. For the digital implementation of control algorithms, discretization of equations and recurrence relations for the rotor angular velocity and blade orientation angle are used. A simplified representation of torque and resistance in the form of polynomial dependencies provides sufficient accuracy with minimal computational costs and allows for effective testing of control algorithms in real time. The proposed model adequately reproduces the dynamic characteristics of the installation, takes into account stochastic wind factors, and allows for the implementation of digital control systems with high blade orientation accuracy. The use of the model ensures increased stability and efficiency of rotary-blade wind power installations in real operating conditions, guarantees reliable electricity production under variable weather conditions, and preserves the key dynamic properties of the system with minimal resource consumption. Recieved 2025-12-07 Recieved 2026-02-02 Accepted 2026-02-11
Multi-agent deep reinforcement learning in the path planning problem
This work is devoted to multi-agent deep reinforcement learning in the path planning problem. The use of UAV swarms in precision agriculture is justified. It is shown that for the use of drone swarms it is necessary to apply artificial intelligence, in particular reinforcement learning. The task of path planning in the presence of poor quality or absence of GPS navigation is set. The use of the Multi-Agent Proximal Policy Optimization method is proposed. The results obtained showed high quality of path planning in the presence of obstacles and poor quality or absence of GPS navigation. Recieved 2025-12-27 Recieved 2026-02-02 Accepted 2026-02-11
Synthesis of an adaptive control system for municipal outdoor lighting based on multicriteria optimization
The paper addresses the urgent problem of increasing energy efficiency in municipal outdoor lighting systems, which often operate with excessive power margins. The study aims to enhance the energy efficiency and operational quality of street lighting systems by improving a control system that accounts for natural light levels, luminous flux uniformity indicators, and equipment service life. A mathematical model of the spatial light field distribution has been developed, and the automatic lighting level control problem is formulated as a multi-objective optimization task. To find a compromise solution between minimizing energy consumption and maximizing both lighting uniformity and equipment resource, the method of approaching the "ideal (utopian) point" in the criteria space using the Chebyshev metric was applied. Numerical simulation for a typical highway section confirmed the effectiveness of the proposed approach. It was established that the adaptive system provides a reduction in power consumption by 27.9% (from 600 W to 432.6 W) compared to traditional timer-based systems. Savings are achieved by compensating for the natural background and eliminating the technological lighting margin — reducing the minimum level from 20.02 lx to the standardized 15.00 lx. Simultaneously, longitudinal uniformity is increased from 0.778 to 0.790, and the predicted service life of the luminaires is nearly doubled (up to 100,000 hours) due to reduced thermal load. The implementation of this method enables the creation of Smart City class systems that adapt to real-world visibility conditions, guaranteeing traffic safety at minimal operational costs. Recieved 2025-11-07 Recieved 2026-01-05 Accepted 2026-02-11
Influence of the specific heat capacity of the raw material fermented in a biogas reactor on the heat distribution
Every year, the use of biogas technologies gives impetus to the development of new methods of handling accumulated waste from agricultural and household facilities. Therefore, the current issue is to reduce energy costs for maintaining the microclimate of fermentation, with the maximum possible formation of biogas from a certain type of raw material. Physico-chemical parameters have a significant impact on the fermentation of raw materials and energy costs. The purpose of the work is to analyze the impact of the specific heat capacity of the raw material fermented in a biogas reactor on the change in the Prandtl criterion and energy costs for heating. The results of theoretical studies are presented, during which the impact of the range of specific heat capacity of raw materials from 1000 to 4000 J/(kg 0C) on energy costs was analyzed The result is graphical dependences that describe the change in the heat transfer coefficient and heat transfer from the heating device to the raw material, the change in the Prandtl and Reynolds criteria depending on the change in the specific heat capacity of the raw material and the speed of rotation of the mixing device. The percentage change in the Reynolds criterion, heat transfer coefficients and heat transfer when changing the speed of rotation of the mixing device is established. It is established that the change in the Prandtl criterion depending on the change in the specific heat capacity of the raw material occurs according to a linear law. The use of the obtained results in combination with previous studies concerning the influence of physicochemical parameters on energy consumption gives an impetus towards establishing a rational speed of rotation of the mixing device from the point of view of energy consumption. Recieved 2025-11-27 Recieved 2026-01-19 Accepted 2026-02-11
Smart campus: implementation of energy innovations in the educational environment
The article considers approaches to increasing the energy efficiency of higher education institutions in the context of digitalization using the example of the implementation of the Smart Campus concept at the National University of Life Resources and Environmental Sciences of Ukraine. The main attention is paid to the use of automated energy monitoring systems that provide continuous control of electricity and heat consumption in real time. The possibilities of using the collected data for modeling and forecasting energy consumption, taking into account technical, climatic and behavioral factors, are analyzed. It is shown that the integration of digital tools allows you to identify inefficient operating modes of engineering systems, optimize loads and reduce energy consumption. The results of studies of the dynamics of energy consumption in educational buildings and dormitories are presented, which demonstrate the adaptability of the system to changes in operating conditions and user stay modes. The effectiveness of the use of analytical and predictive models to improve the quality of energy management and reduce energy and financial risks is substantiated. It was established that the implementation of energy monitoring systems contributes to reducing energy consumption, increasing the energy efficiency of buildings and forming a culture of rational use of resources. The educational and scientific value of the system as a tool for training specialists in the field of energy management and digital energy technologies is also emphasized. Recieved 2025-11-17 Recieved 2026-01-09 Accepted 2026-02-11
Concept of construction of the electrical complex for monitoring and regulation of the biogas reactor operation mode
This article focuses on improving the operational efficiency of existing biogas plants through the implementation of an electrical system based on a submersible multifunctional electromechanical converter (PEMC). The aim of the study is to develop a concept for a system to monitor and regulate the operating mode of a biogas reactor. The system combines active thermomechanical and electromagnetic effects on the substrate with distributed intelligent monitoring. The system’s architecture is based on the synergistic interaction of two functional subsystems: the PEMP—an actuator located directly within the reactor’s working volume that provides simultaneous mixing, heating, and magnetization of the substrate, spatial temperature monitoring, rotation speed control, and, if necessary, the intensity of the magnetic field in the external rotor array; a device for automatic parameter control—a measurement module that provides periodic, high-precision monitoring of physicochemical parameters (pH, Redox, density, O2, NH3, H2 content, etc.) with an automatic maintenance function (cleaning and calibration) for the sensors. This allows for the transition to comprehensive fermentation control, where thermal and mechanical flows are formed adaptively to the state of the medium. To evaluate the dynamic properties of the rotary transformer, a series of measurements was conducted on an experimental sample while varying the frequency of the input P-wave signal. It was found that the most balanced parameters were observed at 2 kHz: sufficient induced voltage and moderate short-circuit current. Future development prospects include linking the assessment of the methanogenesis process not only to the influence on the substrate through changes in operating parameters inside the bioreactor, but also to the conditions affecting the pretreatment of raw materials (primarily lignin-containing ones). Recieved 2025-12-01 Recieved 2026-01-21 Accepted 2026-02-11
Mathematical model of electricity consumption by enterprises of the chernihiv region
The article examines the dynamics of electricity consumption by enterprises in Chernihiv Oblast and presents a forecast of electricity consumption for 2026. The relevance of the study is determined by the need to improve the efficiency of energy resource management in enterprises under conditions of economic instability caused by the full-scale war in Ukraine and the global energy crisis. Therefore, issues of energy consumption planning, ensuring the continuity of production processes, and improving energy efficiency are becoming particularly important for the stable functioning of the regional economy of Chernihiv Oblast. The aim of this study is to develop a mathematical model and forecast electricity consumption by enterprises in Chernihiv Oblast based on statistical data for the period 2016–2024. Official data from the State Statistics Service of Ukraine on electricity consumption for production, operational, and business needs of enterprises, excluding electricity supplied to households, were used in this study. Methods of descriptive statistics, correlation analysis, and regression analysis implemented in Microsoft Excel were applied. As a result of the correlation field analysis, several types of regression models were considered. The cubic polynomial function proved to be the most suitable, with a coefficient of determination R² = 0.9303, indicating a high level of agreement between the model and empirical data. Based on the constructed empirical polynomial model, a point forecast of electricity consumption for 2026 was obtained, amounting to 724,274 thousand kWh. The results of the study can be used for planning and improving the efficiency of energy resource management in Chernihiv Oblast. Future research prospects include extending the model by incorporating dominant influencing factors and applying machine learning methods. Recieved 2025-11-27 Recieved 2026-01-30 Accepted 2026-02-11
Contactless gesture-based control of smart agricultural devices
The purpose of this study is to develop a scientifically grounded approach to the design of ergonomic control systems for information models of agricultural unmanned aerial vehicles based on hand gesture recognition algorithms using modern computer vision and deep learning technologies. The proposed approach aims to improve the efficiency, accuracy, and usability of human–machine interaction in real-world agrodrone operation. The study applies system analysis methods to formalize the “user–device” interaction, as well as comparative analysis of modern software libraries and frameworks (MediaPipe, OpenCV, TensorFlow, PyTorch). Methods of deep learning, including convolutional neural networks, are used to solve hand gesture recognition tasks. Simulation modeling using Python is employed to test and validate the developed prototype. A methodology for designing an ergonomic gesture-based control system for agro-drones has been developed. It includes the formalization of the interaction model, justification of a gesture set based on ergonomic criteria, selection of software tools, and determination of neural network architecture parameters. An experimental prototype based on MediaPipe and Python has been implemented, providing real-time gesture recognition. Simulation testing using cursor control modeling was conducted to evaluate recognition accuracy and stability. The obtained results confirm the operability of the proposed approach and demonstrate its practical applicability for developing intuitive control interfaces for agro-drones. The proposed approach improves human–machine interaction efficiency through the use of natural gesture interfaces and adaptive recognition algorithms. The developed methodology can be applied not only to agro-drones but also to other smart devices. Experimental results confirm the feasibility of applying computer vision and neural networks for contactless control systems, opening prospects for further research in improving accuracy, robustness, and integration into real cyber-physical systems. Recieved 2025-11-20 Recieved 2026-02-01 Accepted 2026-02-11
Features of identification of grain thermal processing
The article considers the processes of heat and mass transfer during convective drying of grain material. The purpose of the work is to develop and identify a mathematical model of grain heating and drying kinetics, taking into account variable thermophysical properties of the material. As a basic model, a system of differential equations proposed by O.V. Lykov is used for a thin grain layer, considering the non-stationary nature of the process and the dependence of moisture diffusivity coefficients on the temperature and moisture content of the grain kernel. A simplified analytical relationship for the drying coefficient is proposed, which makes it possible to reduce the computational complexity of the analytical solution of the model without loss of accuracy. Model parameters were identified based on experimental data using the inverse problem method and the analytical solution of the proposed mathematical model. Empirical dependences of the model coefficients on the initial grain moisture content and the main operating parameters of the drying process were obtained. The results of numerical simulation using the model with identified variable coefficients show good agreement with experimental data, which is confirmed by a high value of the multiple correlation coefficient (R = 0.96–0.99). The proposed mathematical model with variable identified coefficients can be used to predict grain drying kinetics when determining rational operating modes of grain dryers and developing intelligent control systems aimed at increasing the energy efficiency of the process while maintaining grain quality. Recieved 2025-12-01 Recieved 2026-02-01 Accepted 2026-02-11
Influence of voltage deviation on the drive characteristics of working machines with dc motors of independent and parallel excitation at the torque of static supports linearly dependent on the angular velocity
Studies on the influence of voltage deviation and asymmetry on the technological and energy characteristics of working machines and mechanisms with an asynchronous electric drive have shown that when they deviate, productivity decreases and specific energy consumption increases. However, there are no studies on the influence of voltage deviation on DC electric drives. The purpose of the study is to establish the influence of voltage deviation in electric drives with DC motors of independent and parallel excitation on the technological and energy characteristics of working machines with a static resistance moment that depends linearly on the angular velocity. When the voltage deviates, the angular velocity of DC motors of independent and parallel excitation changes, which causes a change in the productivity of the working machine. In DC motors of independent and parallel excitation with a saturated magnetic system, the dependence of the productivity of the working machine on the voltage change is linear. When the voltage deviates, the constant and variable power losses change in the DC electric motor. It is proposed to conduct an energy assessment of a DC electric drive based on specific electricity consumption. The study of the influence of voltage deviation on the energy characteristics of working machines with a static resistance moment linearly dependent on angular velocity, which are driven by DC motors of independent and parallel excitation, was carried out. It was established that when the voltage decreases, the specific electricity consumption decreases. Recieved 2025-12-12 Recieved 2026-01-27 Accepted 2026-02-11
Ontology-based decision support system in entomophages production
The article explores the issue of developing a decision support system based on ontologys in the production of entomophages for the biologization of plant protection, which is due to the need to increase the efficiency of the management processes of this production. The use of ontologies makes it possible to generalize and systematize knowledge about the processes of entomophages production based on the results of previous research, technological experience of specialists, analysis of scientific papers, and modern software tools. The aim of the study is to develop a decision support system based on ontologies in the production of entomophages. Research methods – systemic and synergistic approaches, ontological engineering, machine learning, publicly available software environments Visual Understanding Environment and FreeMind, and the Scilab computer mathematics system. An analysis of recent research and publications on the creation of decision support systems based on ontologies was conducted. A decision support system based on ontologys in the production of entomophages has been developed, the structure of which is presented in the form of an associative map using the FreeMind software environment. The components of the system are the Visual Understanding Environment software environment; user interface; ontological knowledge base, which contains classes, concepts and built-in ontologies. System functions: decision-making support regarding the quality of entomological products and the level of technological controllability of production processes under conditions of uncertainty; automated analysis, structuring and digitalization of knowledge. The research results allow to increase the level of automation of processes for managing the production of entomophages and the competence of the decision-maker, and can be used in the creation of artificial intelligence systems in the production of biological plant protection products Recieved 2025-12-25 Recieved 2026-01-12 Accepted 2026-02-11
Substitution of the principles of balancing micro power systems with power deficit and consideration of consumer categories by using cyclic outage schedules
As a result of massive missile and drone attacks on the energy infrastructure, there is a power shortage in most regions of Ukraine, which causes emergency and stabilization outages. Under such conditions, it is important to effectively use the available energy potential to maintain the viability of regional energy systems, taking into account the power limit. The legislative and regulatory framework regulates the application of hourly and emergency outage schedules and power consumption restrictions, determining the priority of reliable power supply to critical infrastructure facilities. Connecting consumers of different priorities to common feeders of 6–10 kV consumer substations in real distribution networks significantly complicates dispatching management and requires substantiation of methods for optimizing power flow distribution under variable limits. The purpose of the study is to substantiate a mathematical model of power flow balancing taking into account the criticality of feeders based on cyclic outage schedules by using a mixed-integer model of power flow distribution in the three-level structure of the power island: transmission system operator - distribution system operator - feeders of consumer substations. The model determines the minimum duration of power supply of feeders depending on the load of consumers of the critical group, taking into account the power limit. Numerical modeling was performed for feeders of priority consumers with subsequent minimization of the total power moment as an indicator of flow distribution efficiency. The proposed approach ensures balancing of distribution micro-power systems taking into account the priority of consumers, minimizing electricity losses during network reconfiguration. The practical value of the approach is to determine irrational electricity flows taking into account the network capacity. Further research is related to modeling the balancing of micro-power systems taking into account stochastic regime data and the integration of decentralized sources. Recieved 2026-01-03 Recieved 2026-01-30 Accepted 2026-02-11
The heat recovery equipment features of the application in dusty gas flows
One of the problems hindering the widespread adoption of waste heat recovery systems at many fuel-consuming power and industrial facilities, including waste incineration plants, is the dustiness and aggressiveness of the exhaust gases. Improving fuel efficiency at these facilities is a very actual task. The purpose of the research is to develop efficient heat recovery equipment for waste incineration units and to determine its main structural and operational characteristics. Experimental and computational research methods were used. The results of a complex of these studies on the development of effective heat recovery equipment for dusty gases of fuel-consuming power plants are presented. The experimental research results on heat transfer during waste heat recovery of dusty gases from glass melting furnaces under the conditions of using different heat transfer surfaces were used. These surfaces consisted of steel panel packages constructed from pipes with membranes, finned cast-iron pipes bundles, and steel pipes bundles with annular flow turbulators. An analysis of the thermal efficiency, heat transfer coefficient, and thickness of dust deposits on panel packages was performed, and rational their cleaning intervals were determined. The research results indicate high thermal efficiency of panel surfaces. A technical solution for a panel air-heating heat recovery exchanger for heat recovery of exhaust gases from waste incineration plants has been developed. The heat recovery exchanger is characterized by high thermal efficiency, corrosion-resistant heat exchange surfaces, and the possibility to clean these surfaces of dust layer. Calculation studies of the proposed heat recovery exchanger efficiency in different its operation modes during the year were performed, namely: at different inlet exhaust gases temperatures and ambient, exhaust gas humidity, excess air ratio, dustiness level of the heat exchange surface, etc. The main operating characteristics of the heat recovery exchanger under different operating modes have been determined. In particular, it is shown that, under the conditions considered, its heating capacity value decreases by 1.2-1.4 times at the maximum dustiness level of the heat exchange surface. Recieved 2025-11-27 Recieved 2026-01-16 Accepted 2026-02-11
Technical implementation and study of an experimental stand of an autonomous power supply system with a switched reluctance generator at variable speed
An experimental stand of an autonomous power supply system based on a DC machine simulating a variable speed prime mover and a switched reluctance generator is considered. Generalized and complete structural diagrams of the experimental stand are presented. The operating principle of individual structural elements of the stand is described. The process of self-excitation of a generator from a residual flux is considered and an oscillogram of this process is presented, illustrating the nature of the change in the output DC voltage. Using the oscillogram of the phase current of the generator, the movement of energy in the electric machine – semiconductor converter system is considered. The operating characteristics of a switched reluctance generator were investigated. The experimental data confirm the possibility of using the stand as an autonomous power supply system at variable speed. Key words: DC motor, switched reluctance generator, generated power
Copyright (c) 2025 Energy and Automation https://creativecommons.org/licenses/by-sa/4.0
Research on the influence of the dynamic viscosity of raw material fermented in a biogas reactor on heat distribution
Biogas plants are becoming increasingly popular among industry and domestic consumers. This has led to increased interest in conducting research to increase the profitability of such plants. First of all, researchers are focusing their attention on creating systems that will satisfy the conditions for anaerobic digestion and at the same time consume a minimum amount of electrical energy for mixing and heating the substance. After all, for fermentation, raw materials with different physicochemical composition are used, which significantly affects energy costs. The aim of the work is to study the influence of the dynamic viscosity of the raw materials fermented in a biogas reactor on the change in the Reynolds criterion and heat transfer coefficients from the rotating heater to the raw materials. The article presents a mathematical model for conducting theoretical studies. The work considers the change in the dynamic viscosity of the substrate in the range from 0.01 to 0.1 Pa·s. It was found that when the dynamic viscosity of the raw material changes in the range from 0.01 to 0.1 Pa·s, the Reynolds criterion and heat transfer coefficients change according to an exponential law, which is confirmed by the graphical dependencies obtained during the research and presented in this work. The results obtained will further allow us to establish a rational rotation frequency of the mixing device combined with a heating device, taking into account the change in the dynamic viscosity of the raw material, to create and maintain a favorable microclimate for the anaerobic process with the maximum possible formation of biogas. Key words: reynolds criterion, energy consumption, heat transfer coefficient, dynamic viscosity of raw materials, fermentation, heat transfer coefficient, mixing
Mathematical modeling of the propagation of electroacoustic shear waves in a layered periodic medium “Piezoelectric - gap”
The paper developed a method for constructing dispersion relations for bulk, surface and normal electroelastic shear waves propagating in layered-periodic media formed by repeating a "generating" package consisting of a piezoelectric layer and a vacuum layer that does not have electrical properties. As a result of the analytical calculations, dispersion relations for surface, normal and bulk electroelastic shear waves were obtained. CdS was considered as a piezoelectric material. The obtained dispersion relations were numerically analyzed for different layer geometries and physical properties of materials forming the "generating" package. . Numerical analysis showed that a feature of the obtained bulk wave spectrum is that in the range of changes in the wave number and circular frequency, the zone boundaries do not intersect. The spectrum of normal waves is formed by a set of dispersion curves, which is localized in the zones of transmission of bulk waves except for one dispersion curve from the set. This curve is a dispersion curve for surface modes. The set of dispersion curves of normal modes consists of n curves (n is the number of electroelastic "generating" packages in the structure). The influence of the physical-mechanical and geometric parameters of the layers on the structure of the blocking and transmission zones has been studied, and the influence of the piezoelectric effect has also been investigated. Based on the approaches proposed in previous works, the problems of bulk, surface and normal electroelastic waves are reduced to the study of the properties of the transmission matrices of the "generating" package of layers, through the elements of which the desired dispersion relations are expressed. In the work, it was possible, using the condition of metallization on the outer surfaces of the package, to write the dispersion relations through the elements of the second-order matrices instead of the fourth, which made it possible to simplify the analysis of the dispersion equations. Key words: bulk, surface and normal shear waves, periodic layered structure, piezoelectric, layer with vacuum properties, transmission zones, blocking zones of bulk waves
Research installation for growing plants in a high voltage electric field and under various optical radiation
The study of the influence of high-intensity electric fields and various optical radiation on plant growth and development is a promising direction in agronomy and agroecology. The aim of this work is to develop and test an experimental setup that allows creating controlled conditions for growing plants under the influence of electric fields and optical radiation of various spectra. The setup consists of a system for creating high-intensity electric fields, LED light sources, a climate chamber, and a monitoring and data analysis system for recording growth parameters and physiological processes of plants. The main goal of the study is to assess the effectiveness of the influence of these factors on photosynthetic activity, growth rate and plant yield, as well as to determine the optimal parameters for stimulating their development. Experiments have shown that electric fields can significantly increase the growth rate of plants, and light spectra (red, blue, ultraviolet) affect the efficiency of photosynthesis and the development of the root system. In addition, the combined effect of electric fields and optical radiation helps to improve crop yield and plant resistance to stress factors such as diseases, pests and extreme climatic conditions. High-voltage electric fields also play an important role in stimulating plant growth. The effect of electric fields on biological objects is widely studied in various fields of science, in particular in agronomy. It has been established that electric fields can affect plant growth by stimulating ionic and electrochemical processes in cells, which improves the absorption of water and nutrients from the soil. This opens up new opportunities for improving the quality and quantity of the crop. Key words: electrotechnological complex, energy efficiency, high-voltage electric field, automation
Visual assessment of raw materials in premix production using OpenCV
The quality control of premix components is a crucial stage of their production. It directly influences a number of final product characteristics, including homogeneity, granulometric properties, and the effectiveness of the premix ingredients. This study highlights the relevance of using computer vision based on the OpenCV library for image processing of salt samples, as well as the application of deep learning with TensorFlow for automated quality classification. The results indicate whether the proposed tools are suitable for an efficient quality control process, enabling a reduction of human factor influence and improving the accuracy of defect detection. Key words: computer vision, salt quality assessment, premix production, machine learning, OpenCV, TensorFlow
Modeling of a solar photovoltaic converter in the specialized Matlab software
The developed model of a solar photovoltaic converter (SPC) based on a single-diode model, taking into account shunt and series resistances, photocurrent, and diode reverse current, is used for analyzing the electrical characteristics of the SPC and determining the maximum power point (MPPT) under varying illumination and temperature conditions. The model is implemented in the MATLAB environment, providing the capability for straightforward simulation of physical processes in photovoltaic cells. The proposed method allows obtaining accurate current-voltage characteristics, taking into account the temperature and illumination of the SFС. The implementation of the model in MATLAB simplifies and accelerates its use for the study of MPPT algorithms and autonomous photovoltaic systems. The built-in MATLAB algorithm is used to calculate the current, since the equation of one diode is transcendental and nonlinear with respect to current, and direct analytical methods do not solve it. The results obtained will increase the speed of obtaining current-voltage characteristics of the SFС and determining the maximum power point without the need for lengthy experimental measurements. This will accelerate the development and optimization of autonomous and integrated photovoltaic systems, evaluate the efficiency of the SFP under various conditions, and also simplify testing and verification of MPPT algorithms in the MATLAB environment. Key words: solar photovoltaic converter, resistance, current-voltage characteristic, voltage source, mathematical model
The thermal method in the diagnostic and protection system of an electric motor
Induction motors (IMs) are the most widespread electrical consumers in port and ship electrical complexes. The share of IMs among all electrical receivers operating at voltages up to 1000 V reaches up to 70 % of the total number. The main factor that shortens the service life of electric machines operating under conditions of increased dustiness of the environment is the accelerated aging of stator winding insulation. The dust layer thickness on the upper part of the end winding of motors with a power of 50 kW or more ranges from 2 to 5 cm. The accumulation of dust on the surface of the IM winding insulation leads to reduced heat dissipation and local overheating of the insulation under the dust layer. The development of a method for diagnosing the causes of thermal loading of stator winding insulation and a system for thermal protection of IMs, determining the conditions for preventive maintenance, as well as creating algorithms and software for devices providing thermal protection of induction motors, is therefore a relevant task. Key words: induction motor, thermal protection, local overheating of insulation, software, thermal protection of an electric motor
Development of a training stand based on the MKN1063 cabinet for the practical preparation of students in electrical installation and automation
The article presents the results of a study aimed at addressing the problem of insufficient practical training of students in electrical engineering specialties in the areas of installation, commissioning, and operation of electrical equipment. An analysis of the industrial internship conducted at the company LLC "SichEnergo" revealed that a significant portion of students lack the necessary competencies to work with cabinet electrical equipment. In particular, difficulties were identified during installation work in the confined spaces of electrical cabinets, insufficient skills in cable routing, installation of modular equipment on DIN rails, execution of switching operations, and connection of circuit breakers, relays, contactors, PLCs, and other apparatus. A separate methodological issue was the impossibility of organizing group training directly at real, operating cabinets due to limited access to the working area. A review of current research in the field of engineering education showed that, despite the development of VR/AR technologies, digital simulators cannot fully replace physical installation stands. Virtual tools are effective for visualizing and familiarizing students with system construction principles; however, detecting and correcting cable connection defects, proper use of tools, organizing the installation space, and performing operations in real conditions require hands-on work with actual components. Therefore, the optimal training model is a combination of digital technologies and physical constructions that can accurately simulate the production environment. To address this issue, a universal training installation stand was developed based on the industrial MKN1063 electrical cabinet. The stand's design includes typical electrical installation components, programmable logic controllers, modular relays, circuit breakers, communication modules, and other equipment, allowing students to practice both basic and advanced training scenarios aligned with modern production requirements, including Smart Grid and IoT infrastructure. The stand is equipped with transparent side panels, enabling the entire group to simultaneously observe the installation process, analyze execution techniques, and correct errors. A key innovation of the stand is the ability to perform installation first on a horizontally placed panel and then on its vertical placement inside the cabinet. This approach allows for accurate replication of real production conditions, practice of the full installation cycle, and development of competencies required for working with cabinet equipment. The modular layout provides flexibility in configuring training tasks, including disassembly, troubleshooting, and maintenance operations. Results of the trial implementation demonstrated increased accuracy in performing installation tasks, improved teamwork skills, and higher compliance with electrical safety requirements. Key words: installation of electrical equipment, control cabinet, panel, stand
System of monitoring and management of electricity consumption in the micro-energy system of a territorial community with own sources
The article considers the practical aspect of organizing the functioning of a microgrid of a housing cooperative of household owners as a prototype for implementing European principles of decentralized energy supply in accordance with the new Law of Ukraine "On the Electricity Market". The study deals with the analysis of the features of structuring microenergy system sources and the principles of implementing monitoring and management of electricity consumption based on the use of modern software and hardware complexes. The advantages of using cloud technologies (Oracle) for data processing, forming electricity consumption balances and forecasting in real time are proven. The authors investigated the possibilities of integrating heterogeneous generation sources (external network, diesel generator, solar power plants, electricity storage systems) into a single microgrid with the ability to operate both when connected to the external network and in isolated mode (in energy island mode) with its own metering and dispatching system. Ways for further development of micro-energy systems of territorial communities in Ukraine are proposed, taking into account European experience and current regulatory and legal support. Key words: microgrid, energy island, decentralized energy supply, monitoring system, electricity consumption management, power balancing
Integrated assessment of the quality of microprocessor-based relay protection
The article discusses the problems of assessing the effectiveness of microprocessor-based relay protection of power system facilities. The relevance of the study is due to the importance of relay protection devices in ensuring timely detection and elimination of emergency modes, preventing equipment damage, and maintaining the stability of the power system. Traditional approaches to assessing performance quality boil down to taking into account equipment and operational losses or are limited to the percentage of correct relay actions, which does not always allow for an accurate assessment of system efficiency. The purpose of the study is to develop an integrated criterion for evaluating the effectiveness of microprocessor-based relay protection, which takes into account functional and metrological losses caused by measurement errors, response delays, and other features of the implementation of protection algorithms. To analyze losses, it is proposed to classify them into groups: functional-metrological, related to the adjustment of settings and the properties of selectivity and sensitivity; indirect hardware, arising from component failures and personnel errors; independent of settings, including damage to equipment and infrastructure. For quantitative assessment of effectiveness, an integral indicator <!-- [if gte msEquation 12]><m:oMath><m:r>m</m:r><m:d><m:dPr><m:ctrlPr></m:ctrlPr></m:dPr><m:e><m:r>E</m:r></m:e></m:d></m:oMath><![endif]--> <!-- [if gte vml 1]><v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="m@4@5l@4@11@9@11@9@5xe" filled="f" stroked="f"> <v:stroke joinstyle="miter"/> <v:formulas> <v:f eqn="if lineDrawn pixelLineWidth 0"/> <v:f eqn="sum @0 1 0"/> <v:f eqn="sum 0 0 @1"/> <v:f eqn="prod @2 1 2"/> <v:f eqn="prod @3 21600 pixelWidth"/> <v:f eqn="prod @3 21600 pixelHeight"/> <v:f eqn="sum @0 0 1"/> <v:f eqn="prod @6 1 2"/> <v:f eqn="prod @7 21600 pixelWidth"/> <v:f eqn="sum @8 21600 0"/> <v:f eqn="prod @7 21600 pixelHeight"/> <v:f eqn="sum @10 21600 0"/> </v:formulas> <v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect"/> <o:lock v:ext="edit" aspectratio="t"/> </v:shapetype><v:shape id="_x0000_i1025" type="#_x0000_t75" style='width:33pt; height:16.5pt'> <v:imagedata src="file:///C:\Users\SVV\AppData\Local\Temp\msohtmlclip1\01\clip_image001.png" o:title="" chromakey="white"/> </v:shape><![endif]--> is proposed, which takes into account all elements of the relay protection channel and allows assessing the probabilistic characteristics of losses and the potential effect of protection. To assess reliability, a normalized failure rate <!-- [if gte msEquation 12]><m:oMath><m:sSub><m:sSubPr><m:ctrlPr></m:ctrlPr></m:sSubPr><m:e><m:r>m</m:r></m:e><m:sub><m:r>∑</m:r></m:sub></m:sSub></m:oMath><![endif]--> <!-- [if gte vml 1]><v:shape id="_x0000_i1025" type="#_x0000_t75" style='width:19.5pt;height:18pt'> <v:imagedata src="file:///C:\Users\SVV\AppData\Local\Temp\msohtmlclip1\01\clip_image003.png" o:title="" chromakey="white"/> </v:shape><![endif]--> is used, which includes relay failures, incorrect protection actions, and personnel errors. An integrated approach allows for a comprehensive assessment of the efficiency, technical excellence, and economic feasibility of using microprocessor relay protection devices, predicting their behavior in emergency situations, optimizing settings, and increasing the adaptability and reliability of the system in real operating conditions. The use of the probabilistic-statistical method ensures objectivity of assessment and allows making informed decisions on the modernization and optimization of relay protection systems for power facilities. Key words: wind power installation, wind potential, wind speed, repeatability of wind speeds, distribution function, forecasting
Thermal load of buildings as a parameter of energy efficiency of the heating system
Reducing heat energy consumption and increasing energy efficiency at all stages of heat transformation in district heating systems is a key measure to combat climate change, which is the goal of the EU energy policy. The value of the calculated heat load (CHL) is the basis for determining the heat carrier consumption in the heat networks of district heating systems. However, the inconsistency of regulatory documentation and changes taking place in the field of heat supply have led to the fact that today there is no generally accepted methodology for determining this value. The purpose of the study is to compare existing methods for determining the value of CHL for heating needs and to provide recommendations for the correct determination of this indicator for different categories of buildings. The general principles of calculating the heat load for heating and ventilation systems of residential and public buildings are considered. Problems that arise during the determination of the value of the connected heat load for district heating systems are noted. Recommendations are given on ways to solve such problems/ Key words: connected heat load, calculated heat losses, thermal resistance, heating and ventilation
Impact of solar energy application on improving the energy performance of continuous-flow heat pump grain dryers
Grain drying is an essential stage of post-harvest processing. Utilizing renewable energy sources, particularly heat pumps combined with solar energy, is one of the methods for improving the process's energy efficiency. Brief information is provided on the use of heat pumps in combination with various approaches to solar energy utilization. A detailed schematic diagram of a continuous-flow grain dryer is considered, which involves the sequential use of two drying agent heating systems: a solar air heater and a heat pump. Within the scope of this article, an analytical model for determining the energy efficiency of this schematic solution is presented along with the calculation results. Recommendations are provided for the optimal use of the heat pump in combination with the solar heater in continuous-flow dryers with drying agent recirculation. The research findings will be useful for further scientific research and for developers of modern grain drying systems. Key words: grain dryer, energy efficiency, recirculation, heat pump, solar collectors, solar heat pump, solar energy, recuperation, flow dryers, grain moisture
Development of new heat exchanger design for the use of exhaust gases of ice in cogeneration plants. Hydraulic calculation
New design of heat exchanger for utilization of exhaust gases of an internal combustion engine, which is part of cogeneration plant, is proposed. This design differs from traditional designs by the presence of compact bundles of small diameter pipes in the absence of gaps between adjacent pipes in the longitudinal direction of gas coolant. Method of hydraulic calculation of heat exchanger-utilizer has been developed, which makes it possible to determine the power of smoke exhauster when removing combustion products and pump for pumping water coolant. It was found that new design of heat exchanger has significantly lower pressure losses in the intertube channel of heat exchanger-utilizer compared to known designs. Capacities of smoke exhauster and water pump have been determined, which can be used when selecting heat energy equipment for cogeneration plants based on internal combustion engines.
The influence of stator winding resistance imbalance of an induction motor: evaluation of phase current asymmetry
Asymmetry of the active resistances of stator windings occurs in approximately 30 % of repaired induction motors operating in power complexes of seaports, industrial enterprises, and ships. The resistance asymmetry causes current imbalance in the windings even under symmetrical supply voltage. In a non-symmetrical network, the asymmetry of active resistances can both increase and decrease the current asymmetry coefficient. The use of the Mathcad system enables the calculation of the current asymmetry coefficient depending on the deviation of the supply voltage, variation of stator winding resistances, load current, and supply frequency. Key words: induction motor, active resistance asymmetry, voltage asymmetry, current asymmetry coefficient
Investigation of spectra and of aggregation of vanadium phtalocyanine molecules in two-component solutions
It was studied the electronic spectra of vanadium phtalocyanine dye molecules in diluted and concentrated solutions as well as in low- and high-polarity solvents. In diluted low-polarity solvent VOPc molecules exist in monomer state, whereas dye molecules concentration increase leads to appear of dimer formation. It was shown that using of mixed acid-water solvent is an effective approach to controlled aggregation of dye molecules. Main parameters of the influence on VOPc aggregation are concentration of water ingredient and associates “growth” time. In a concentrated high-polarity solvent, the dye molecule is in the form of a monocation solvated by solvent molecules and unable to interact with other dye ones. In this case, it is just the monomolecular absorbance spectrum that is characteristic for the solution. As water is added, the dye molecular interaction becomes possible due to the solvatic shell destruction, and association of organic molecules occurs. In our case, this results in the appearance of a broad 980 nm band in the absorbance spectrum. Using acid-water mixtures and varying the water concentration therein, the dye aggregation process can be controlled as well as the number of molecules in an aggregate. So the appearance of absorbance bands at 775 and 690 nm is observed which can be attributed to the formation of sandwich-type dimers (H-dimers). As the water concentration increases, large dye aggregates are formed. At high water concentrations, micro-scale single crystals may grow. The “growth” process can be observed in absorbance spectra as the appearance of the 980 nm band and its further intensity increase, long-wavelength shift and broadening. Above features demonstrate an approach to size-controlled preparation of dye molecules aggregates in polar – non-polar solutions mixture for farther use in photovoltaic and sensors applications. Key words: nano-size organic dye crystals, association of dye molecules, enhancement of electronic properties of aggregated dye molecules, seft-assembling of molecules
Comprehensive assessment of power quality in a low-voltage node with distributed generation and energy storage: evidence from field monitoring
The objective of this study is to conduct a comprehensive assessment of power quality parameters in a low-voltage node incorporating photovoltaic modules and an energy storage system, based on long-term field monitoring. The methodology involved analyzing time series of voltages, currents, active power, power factor, and total harmonic distortion recorded with a 15-minute resolution during the period September 2024 – March 2025. Data were segmented according to import and export modes of energy flow, resampled, and subjected to event-based detection of intervals deviating from EN 50160 and IEEE 519 standards. The results demonstrated that voltage consistently remained within permissible limits, whereas approximately 81% of measurements indicated current harmonic distortion exceeding 5%. The absolute power factor was not lower than 0.9 in 90% of cases, but declined to 0.85–0.90 in nearly 10% of intervals, primarily due to harmonic distortion and reactive power exchange. Moreover, the analysis confirmed the high stiffness of the supply network, which accounts for the stability of voltage parameters despite pronounced current harmonics. The findings underline the necessity of implementing active or passive filtering measures to mitigate harmonic distortion and maintain power factor stability. Key words: power quality, harmonic distortion, power factor, grid stiffness, short-circuit capability, low-voltage networks, municipal facilities