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E-Journal №3(67)2025

"PROBLEMS of the REGIONAL ENERGETICS (https://doi.org/10.52254/1857-0070.2025.3-67)"

CONTENTS

1	Traction Drive Control System for Railway Electric Rolling Stock Based on the Application of Power Factor as an Optimization Criterion Authors: 1Goolak S., 1Gorobchenko O., 1Holub H., 1Kulbovskiy I., 2Petrychenko O. 1National Transport University, Kyiv, Ukraine 2National University “Odessa Maritime Academy”, Odesa, Ukraine
	Abstract: The objective of this work is to provide theoretical substantiation for the possibility of using power factor as a criterion in the development of optimized automatic control systems for AC electric rolling stock traction drives. The stated objective has been achieved through the solution of the following tasks: development of an algorithm for applying traction drive power factor as an optimization criterion, taking into account stochastic disturbance effects acting on the traction drive from the traction power supply system and mechanical load; development of a structural scheme for an optimized automatic control system of electric rolling stock traction drives, in which the proposed algorithm is implemented. The most important results are: the obtained analytical time dependency of the traction drive power factor, representing a convolution of two-time functions—efficiency and active power utilization coefficient of the traction drive—and the developed algorithm for eliminating stochastic disturbance effects acting on the traction drive from the traction power supply system and mechanical load. The significance of the obtained results lies in improving the quality of AC traction drive control. An electric locomotive traction drive with field-oriented control (FOC) of asynchronous traction motors was selected as the research object. This will enable improved regulation quality in the construction of an optimal automatic control system for traction drives.
	Keywords: power factor, energy-efficient traction drive control, time function convolution, microprocessor control system. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.01
2	Short-term Power Load Forecasting for a 33/11 KV Sub-Station by Utilizing Attention-Based Hybrid Deep Learning Architectures Authors: Mukkamala R, Sunku V.S., School of Energy & Clean Technology, NICMAR University of Construction Studies, Hy-derabad, Telangana, India.
	Abstract: Estimating electric power load at substations is a fundamental task for system operators, as it is essential for the reliable and optimal operation of the power system. Effective load forecasting is critical for optimal power generation, as precise predictions facilitate the economical use of electrical infrastructure. The primary objective of this study is to develop advanced deep learning (DL) attention-based models aimed at improving the accuracy of short-term electric power load forecasting at substations. This enhancement is essential for ensuring the reliable and efficient operation of power systems. To accomplish this objective, a comprehensive evaluation of various machine learning (ML) and deep learning (DL) architectures was conducted. This evaluation included the following models: Autoregressive Integrated Moving Average (ARIMA), Multi-Layer Perceptron (MLP), Ran-dom Forest (RF), Gradient Boosting (GB), Long Short-Term Memory (LSTM) networks with Atten-tion mechanisms, LSTM-Convolutional Neural Network (CNN) Attention, etc. These models applied to hourly estimated energy consumption data (in kilowatts) sourced from the 33/11 kV sub-station in Telangana, India. The performance of these models measured using several key metrics, including Mean Squared Error (MSE), Root Mean Squared Error (RMSE), and R-squared (R²). The most important result is that the CNN-BiLSTM attention model significantly outperforms the other models, achieving an MSE of 0.0079, an RMSE of 0.0889, and an R² value of 0.8547. that under-scores that the CNN-BiLSTM attention model represents an effective and practical tool for accurate power load forecasting. This capability not only enables the economical utilization of electrical infrastructure but also supports reliable, data-driven decision-making processes within power system operations.
	Keywords: short-term load, forecasting, deep learning, machine learning, attention-based mechanisms. perfor-mance metrics DOI: https://doi.org/10.52254/1857-0070.2025.3-67.02
3	The European Green Deal Industrial Plan: Risks and Opportunities. The Chances of the Romanian Economy Authors: Strautiu E., Melintei M. Lucian Blaga University of Sibiu Sibiu, Romania
	Abstract: The European Green Deal Industrial Plan (EGDIP), announced by the European Commission to the other institutions and bodies of the European Union on 1 February 2023, aims to achieve a carbon-neutral European community by 2050 by transforming production and consumption paradigms. Main objectifis of the study aimes to describe the objectives, methods, and means of the EGDIP, to assess its chances of success about the challenges and risks it entails, to analyze the geopolitical and international policy implications of the European Union and to provide a case study on the stage Romania is in assuming and implementing this plan. The most important results are to nuance the official text, drawing attention to the needs for coordinating objectives and means with other major global industrial players, distributing efforts in a fair proportion to the current carbon emissions of national economies in the European Union, and adjusting national contributions (financial in the first place) to the real possibilities of economies in crisis. In the case of Romania, we will note the incipient degree of addressing the EGDIP objectives by the central authorities and the relatively more advanced level of involvement of economic agents, in a context in which Romania already produces low carbon emissions - correlated with the small size of the industry in question and the systematic closure of coal mines. The significance of the results obtained is summed up in completing and refining the theoretical foundations on which EGDIP is based, formulating signals and warnings regarding risks and challenges in the implementation of the project – which can help decision-makers and their advisors, university professors, and researchers in the formulation of policies, but can also contribute to additional information for journalists and public opinion.
	Keywords: the European Green Deal Industrial Plan, greenhouse gas emissions, net-zero emissions industry, energy transition, decarbonization. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.03
4	Increasing the Efficiency of the Charcoal Production Process through the Pyrolysis of Woody Agricultural Waste with the Application of Microwaves Authors: 1Popescu V.S., 1Golubev V.P., 2Degterov D.V., 2Vasilevich S.V., 3Asadchyi A.N., 2Shevchik N.E. 1Technical University of Moldova Kishinau, Republic of Moldova 2Institute of Power Engineering of the National Academy of Sciences of Belarus, Minsk, Republic of Belarus 3Belarusian State Aviation Academy Minsk, Republic of Belarus
	Abstract: The purpose of the work is to increase the efficiency of the charcoal production process by pyrolysis of woody agricultural waste with the application of mirowaves. To achieve the goal, an experimental installation was developed, which allows the application of the pyrolysis method with the application of microwaves in the charcoal production process from wood. The research was focused on the example of pyrolysis of woody agricultural waste, but in particular, fruit waste from apple orchards was selected as the main object of the research. These agricultural wastes were specifically researched, because at the moment they have a fairly large share and are not efficiently utilized, and so far no one has studied the possibilities of processing them by pyrolysis and obtaining charcoal from these fruit wastes. The main results obtained with the application of the developed installation are increasing the efficiency of the coal production process by pyrolysis of woody agricultural waste based on the application of the microwaves tartarization method, increasing the speed of the process and, respectively, reducing the processing time and improving the quality of the resulting coal. Thus, the pyrolysis plant with the application of microwaves demonstrated an increase in productivity per unit of time and a high yield of charcoal production from the processed raw material. The significance of these results lies in solving some essential problems in the field with a contribution to the development of the energy sector through the efficient utilization of woody agricultural waste.
	Keywords: wood charcoal, pyrolysis plant, woody agricultural waste, SHF treatment, efficiency, fuel, productivity. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.04
5	Efficiency of Extended Temperature Schedules for Regulation of Heating Networks with Different Shares of Hot Water Supply Load Authors: Suvorov D.M., Tatarinova N.V. Vyatka State University Kirov, Russian Federation
	Abstract: The aim of this work is to study the efficiency of extended temperature schedules for regulating heat supply systems in a wide range of changes in the share of the HWS load. To achieve this aim, the following tasks were solved: initial and extended temperature schedules were calculated and con-structed; calculations of the operating modes of a model CHPP were performed and its energy effi-ciency indicators were determined for both the initial and extended temperature schedules; an analy-sis of the identified dependencies was performed both in a degree-by-degree representation and inte-grally for the entire heating period. The most significant results of the work are the following: for all variants of the calculated parameters, the specific electricity generation with extended schedules is higher than with the initial ones; for any share of the HWS load, the use of extended regulation schedules reduces the specific consumption of equivalent fuel for electricity supply by approximately 1% compared to the initial schedules; the best result for any share of the DHS load is the use of a reduced temperature schedule with a design temperature of delivery water of 110℃. The calculations carried out confirm that for any share of the DHS load, the transition to extended temperature schedules ensures a significant increase in the efficiency of the heat supply system. The significance of the results of the work lies in their applicability for setting and solving problems of ensuring max-imum energy efficiency of heat supply systems based on CHPPs.
	Keywords: heat supply system, delivery water, temperature schedule, initial temperature schedule, extended temperature schedule, specific heat consumption, CHPP, hot water supply load. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.05
6	Study of Asymmetries in 0.4 kV Distribution Line with Different Schemes of Supply Transformers and Connection of Single-phase Renewable Energy Source Authors: Bosneaga V., Suslov V. Technical University of Moldova, Power Engineering Institute Chisinau, Republic of Moldova
	Abstract: The aim of the work is studying asymmetric modes of 10/0.4 kV distribution transformers at connecting single-phase renewable energy sources. This problem is relevant due to increasingly use of such sources. To achieve this goal, calculation of asymmetric modes, asymmetry coefficients for zero and negative sequences and values of phase voltages is performed. This proposed model is novel since it allows analyzing the asymmetry coefficients when connecting single-phase sources directly to distribution transformer low-voltage buses or via supplying three-phase line. Important is that transformer connection diagram is taken into account. It is shown that D/y0 connection has significant advantages over Y/y0 diagram, which is impractical in these modes. When injecting directly onto transformer low-voltage buses, the D/y0 circuit ensures permissible values of phase voltages and asymmetry coefficients in the entire range of injection variation, up to rated current of the transformer. Permissible values of injection via the three-phase line are significantly reduced due to the noticeable negative effect of its zero-sequence impedance. For estimation of injection permissible value depending on three-phase line length and its parameters, it is necessary to calculate the mode. Y/z0 circuit has somewhat better indicators compared to D/y0 circuit. In the case of connecting a single-phase generation source through a three-phase 4-core cable, the permissible value of injection is limited not so much by transformer parameters as mainly by the significantly higher zero-sequence impedance of the cable.
	Keywords: impedance introduced by the transformer and three-phase distribution line, the value of permissible single-phase current injection. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.06
7	Investigation of Inlet Guide Vane Efficiency in Centrifugal Compressors for the Turbo Refrigeration Machines Authors: Danilishin A.M., Kozhukhov Y. V., Fateeva E.S., Aksenov A.A. ITMO University Saint-Petersburg, Russian Federation
	Abstract: The article investigates the influence of geometric parameters of inlet guide vanes (IGVs), including blade profiling and design features, on their operational efficiency. IGVs are widely used in centrifu-gal compressors of turbo-refrigeration machines with various refrigerants to control compressor per-formance by adjusting flow swirl at the impeller inlet. The purpose of the study was to determine the effect of the shape and angle of curvature of the IGV blade profile on its effectiveness when cre-ating a flow swirl at the inlet to the impeller. The study provides theoretical foundations of how in-let swirl affects the aerodynamic characteristics of centrifugal compressor stages. The research method was numerical optimization by computational gas dynamics of the IGV blade profile. The computational domain for numerical experiments consisted of an axial inlet duct with IGV, a mixed-flow impeller, and a vaneless diffuser. Simulations were performed using ideal air as the working fluid under specified inlet atmospheric pressure and outlet mass flow conditions. Approximately 120 IGV flow path configurations were analyzed at four different vane positions. Performance character-istics were derived from numerical simulations, including IGV loss coefficients as functions of di-mensionless geometric parameters and blade shapes. The study established correlations between IGV design variants and performance characteristics, enabling the development of optimal design rec-ommendations. The most significant finding reveals how IGV blade curvature angle critically affects swirl generation efficiency at the impeller inlet. These results contribute to improved efficiency of centrifugal compressors with IGVs in turbo-refrigeration machines using various refrigerants.
	Keywords: inlet guide vane (IGV), centrifugal compressor, turbo-refrigeration machine, CFD simulation, optimization, blade profiling. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.07
8	Modification of Microbial Fuel Cell Anodes via Nitric Acid and Hydrogen Peroxide Treatment for Electrogenic Biofilm Formation Authors: Gladysheva M.S., Molodkina N.R. ITMO University Saint–Petersburg, Russian Federation
	Abstract: The primary objectives of this study are to evaluate the influence of modifying carbon felt electrodes on the formation of microbial electrogenic biofilm and the efficiency of bioelectrogenesis in a two-chamber microbial fuel cell. Microbial fuel cells represent an alternative energy technology that enables the conversion of organic matter into electricity through microbial metabolism. However, their practical application has been limited by low energy efficiency and instability. This research aims to enhance the efficiency of microbial fuel cells by modifying the anodes, which may contribute to the broader adoption of these systems within sustainable energy development. To achieve these objec-tives, the following tasks were addressed: modification of anodes using a mixture of HNO₃ and H₂O₂ to improve the hydrophilic properties and biocompatibility of the electrode surface; long-term re-cording of the system's output voltage to assess the dynamics of electricity generation and to establish correlations between biofilm formation stages and output voltage; and analysis of biofilm structures using light and scanning electron microscopy. Key findings include quantitative indicators of output voltage from two microbial fuel cell configurations. The system with the modified anode demonstrated a significant advantage, exhibiting an output voltage 2.70 to 2.75 times higher than that of the system with untreated carbon felt. The significance of these results lies in confirming the effectiveness of the electrode modification method used, which may facilitate the implementation of microbial fuel cells as alternative energy sources for low-power autonomous devices.
	Keywords: microbial fuel cell, bioelectrogenesis, electrogenic biofilm, microbial adhesion, electrode modifica-tion, carbon felt. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.08
9	Investigation of the Efficiency of using Methane—Hydrogen Mixtures in Fire-Tube Boilers Authors: 1Shaposhnikov V.V., 1Kocharyan E.V., 1Leonova T.A., 1Arushanyan R.R., 2Bezuglov R.V. 1Kuban State Technological University, Krasnodar, Russian Federation 2Platov South-Russian State Polytechnic University (NPI), Novocherkassk, Russian Federation
	Abstract: The aim of the work is to simulate and analyze the efficiency of combustion of methane-hydrogen mixture in an environment with increased oxygen content, and in the limit - in pure oxygen, in a fire-tube boiler to reduce CO2 emissions. To achieve this goal, the following problems were solved: development of a mathematical model of a three-pass fire-tube boiler for operation when burning a natural gas and a methane-hydrogen mixture in air and a mixture of air with pure oxygen, a numeri-cal study of the boiler operation when burning a methane-hydrogen mixture with a hydrogen con-centration from 0 to 40% and replacing air with oxygen from 0 to 100%, assessing the efficiency of equipment in these modes. The most important result is the confirmation of an increase in the effi-ciency of the fire-tube boiler when switching to combustion of methane-hydrogen mixture in an environment with increased oxygen content. The significance of the obtained results lies in determining the most effective parameters of equipment operation, contributing to an increase in the efficiency and environmental friendliness of the heat generation process. The study was conducted for two modes: combustion of a methane-hydrogen mixture with a hydrogen concentration of 0 to 40% in air and combustion of a methane-hydrogen mixture with a fixed hydrogen concentration in air with an oxygen concentration in the range from 0 to 100%.
	Keywords: oxygen combustion, methane-hydrogen mixture, hydrogen, boiler, natural gas, carbon dioxide, modeling, efficiency. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.09
10	Investigation of the Carbon Dioxide Centrifugal Compressor Working Process using Computational Fluid Dynamics Methods Authors: Fateeva E.S., Danilishin A.M., Kozhukhov Y. V., Kazantsev R.A. ITMO University Saint-Petersburg, Russian Federation
	Abstract: The article investigates the carbon dioxide (CO₂) centrifugal compressor using computational fluid dynamics (CFD). CO₂ centrifugal compressors are used in refrigeration and cryogenic systems, power plants with subcritical and transcritical cycles, including Brayton cycle. This work is a part of a re-search effort aimed at developing a methodology for calculating the gas-dynamic characteristics of centrifugal compressor stages in refrigeration systems. The main objectives of the research are to investigate the three-dimensional viscous flow parameters of carbon dioxide in the centrifugal com-pressor flow path using CFD and to compare two approaches of taking into account the reality of gas during modeling comparison. Key tasks included: centrifugal compressor CFD model replicating an experimentally tested compressor geometry and operation, comparing simulated outputs against ex-perimental data, total-to-total isentropic efficiency calculation.Two real-gas modeling approaches were evaluated: Ansys CFX’s built-in real gas models and external tables of CO₂ properties. The most significant results are the describing the features of the carbon dioxide centrifugal compressor working process using both the built-in real gas models in Ansys CFX and imported tables of real gas properties and the demonstration of satisfactory agreement between simulation and experiment. The significance of the obtained results lies in increasing the efficiency of carbon dioxide centrifugal compressors in process units of refrigerating, cryogenic and power systems. Compressors efficiency improvement is provided by developed recommendations application for performance of working process CFD-modeling considering peculiarities of carbon dioxide in subcritical state in design calcu-lations.
	Keywords: centrifugal compressor, carbon dioxide, computational fluid dynamics (CFD), real gas, efficiency, thermodynamic properties, refrigeration systems, power plants. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.10
11	Optimization of Braking Phase Coordinates for Energy-Efficient Operation of Pneumatic Systems Authors: Strizhak M., Rogovyi А., Iglin S. National Technical University «Kharkiv Polytechnic Institute» Kharkiv, Ukraine
	Abstract: The aim of this study is to optimize the operating mode of a pneumatic system by determining the braking start and end coordinates that minimize the piston speed without the use of damping devices. This approach avoids the discharge of compressed air into the atmosphere and brings the operating conditions closer to an energy-saving mode. The goal is achieved through the implementation of a control algorithm that switches the distributor based on the piston position, allowing for the formation of a defined braking trajectory. The study involved mathematical modeling of the transient processes in the pneumatic system, as well as numerical optimization of the braking coordinates using the Nelder–Mead method and exhaustive search. It was found that the optimal braking start and end coordinates should be located within the last 10–15% of the piston stroke to ensure a final velocity of about 0.03 m/s. The most significant result is the development of a generalized dependency between braking coordinates and cylinder stroke length, enabling the design of energy-efficient pneumatic drive modes without the need for additional experimental research. As a result of the optimization, effective piston braking is achieved without damping devices, reducing compressed air losses and increasing the overall energy efficiency of the pneumatic system.
	Keywords: pneumatic drive, braking, commutation, energy efficiency, transient process. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.11
12	Determination of the Energy Efficient Speed of the Working Body of the Agitator for Small Biogas Reactors Authors: Spodoba M.O., Spodoba О.O., Kovalchuk S.I., Oliinik Yu.O. National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
	Abstract: The aim of the work is to determine the energy-efficient speed level of a two-tier paddle mixer with blades installed at an angle of 90° to improve the energy efficiency of the biogas formation process in small biogas reactors. To achieve the set goals, physical methods, three-dimensional modeling, processing and visualization of results in application programs were used. The working hypothesis of the research is that 3D modeling will allow determining the nature of the distribution of biomass flows and the amount of energy expended depending on the rotation speed of the mixing device. The most important result of the study is the obtaining of graphical dependencies of the trajectories of movement of elementary volumes and the velocities of substrate flows at different rotation speeds of the stirrer. The significance of the research results is that, based on the flows of raw materials in the reactor, it was established that for a reactor with the geometric parameters specified in the work, the energy-efficient rotation frequency of the paddle mixer with blades at an angle of 90° is within 40…50 rpm. The average speed of the substance is in the range of 0.273 – 0.348 m/s. It was found that the dependence of the consumed energy on the mixer rotation speed corresponds to a power function. The percentage of useful energy spent in starting and operating modes for different rotation speeds was determined. The obtained data can be used for upgrading and designing mixing systems in small biogas reactors.
	Keywords: energy consumption, small biogas reactors, energy efficiency, modeling, mixing, rotation speed, flow vectors. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.12
13	Bivalent Carbon Dioxide Heat Pump for Heating of Multi-Story Buildings. Part II Authors: Sit M.L., Juravleov A.A., Tirsu M.S., Lupu M.L., Daud V.P., Timchenko D.V. Institute of Power Engineering of the Technical University of Moldova Chisinau, Republic of Moldova
	Abstract: The use of heat pumps is one of the components of the energy transition. The article considers a scheme of a combined heat and power plant with a centralized heat supply system, in which the thermal regime of a number of buildings is ensured by installing heat pumps in them that receive low-potential heat from the return network water and from the outside air. The aim of the work is to create a scheme of a bivalent heat pump (BHP) that uses both the heat of the return network water and the heat of the outside air as sources of low-potential heat (LPH) in the normal operating mode and in an emergency mode, when there is a refusal to supply return network water. The set objective is achieved by solving the following problems: constructing BHP thermodynamic cycles and analyz-ing them, analyzing the operation of the scheme under random disturbances, developing an ACS of the heat pump. The most important results of the work are: a scheme of a heat pump that can func-tion at variable pressures of the evaporator and gas cooler, the introduction of a pre-gas cooler into the BTN circuit, installed before the "coolant-water" gas cooler stage, the control system of which ensures the required temperature of the network water heated by the heat pump of the building. The significance of the obtained results consists in the creation of a BTN circuit, which allows ensuring both qualitative and qualitative-quantitative laws of regulation of the thermal mode of the building in emergency modes caused by the absence of heat supply from the return network water.
	Keywords: bivalent heat pump scheme, automatic control, reliability, district heating, carbon dioxide. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.13
14	Experimental Studies of Elements from the Functional Intermetallic Cu-Al-Mn for Construction of a Heat Engine and Power Plant Authors: 1Kozyrskyi V., 2Bunko V. 1“ALOTEK Technology” company, Poland 2 Separated Subdivision of National University of Life and Environmental Sciences of Ukraine “Berezhany Agrotechnical Institute” Berezhany, Ukraine
	Abstract: The main objectives of the work are to study the thermomechanical characteristics and establish the patterns of reactive force generation by elements made of functional Cu-Al-Mn intermetallic compounds for their further use in heat engines of electrical power generation plants. The objectives were achieved using a test setup with control and measuring instruments to determine the thermomechanical characteristics of elements made of functional intermetallic compounds with different geometric and physical parameters, and by plotting the force-temperature curves. Based on the results of experimental studies, thermomechanical characteristics (dependencies of the reactive force developed by thermosensitive elements on their heating temperature) were constructed, and specific indicators of reactive force generation relative to the mass of thermosensitive elements were determined. It was established that samples at a heating temperature of +90...+100 °C restore their initial shape (after preliminary deformation) in 0.15 s. The specific indicator of reactive force generation relative to the unit mass of thermosensitive elements was determined to be – 0.97 W/g. The significance of the results obtained lies in the fact that the results of experimental studies and the established regularities will be used as a basis for the creation of a heat engine and, on its basis, an electrical installation for the generation of electrical energy operating with low-potential sources of thermal energy – secondary heat energy from technological cycles, water reservoirs of thermal and nuclear power plants, as well as thermal sources.
	Keywords: functional intermetallic, heat engine, electric power generation, shape memory alloy. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.14
15	Passivity Based Control for Interleaved Boost Single-Ended Primary-Inductance Converter for PV System Authors: 1Mohamed Faizal A.A., 2Kar S., 3M.Hullamani R., 4Kavitha P., 5Ananthan N., 6Natarajan K. 1Department of Electrical and Electronics Engineering, VV College of Engineering, Tisaiyanvilai, India. 2Department of Electrical and Electronics Engineering, Medi-Caps University, Indore, Madhya Pradesh, India 3Department of Electrical and Electronics Engineering, Dayananda Sagar College of Engineering, Bangalore, India. 4Department of Electrical and Electronics Engineering, Government College of Engineering, Tirunelveli, India. 5Department of Electrical and Electronics Engineering, Vel Tech Multi Tech Dr Rangarajan Dr Sakunthala Engineering College, Chennai, India. 6Department of Electrical and Electronics Engineering, Trinity College of Engineering and Technology, Peddapalli, India.
	Abstract: This paper addresses the challenges by enabling a novel Interleaved Boost-SEPIC converter (IBSC) for improving the Photovoltaic (PV) system’s performance, controlled by a passivity-based proportional integral control strategy. The use of non-interleaved converters in PV systems leads to reduced efficiency due to challenges in controlling high-frequency switching, potentially resulting in decreased energy conversion efficiency and increased losses. Additionally, non-interleaved converters may exhibit weaker transient response characteristics, leading to slower voltage regulation and potential instability under varying load conditions. There is also a higher risk of electromagnetic interference (EMI) with non-interleaved converters, which can interfere with other electrical systems and equipment. The main objectives of the study are to improve PV system’s performance by enhancing energy conversion efficacy and to provide stable outcomes with improved transient response. These objectives were achieved by the proposed IBSC, controlled by a passivity-based PI controller which aims for efficient regulation of converter voltage output, ensuring high efficiency and rapid transient response. The control scheme utilizes the converter's passive features to guarantee stable operation under various operating conditions. MATLAB simulations establish the robustness of recommended control system, the most important results are rapid transient response of 0.5s, high efficiency of 91% and robust performance for the Boost-SEPIC converter in PV systems. The significance of obtained results includes improved energy conversion, stable voltage regulation and enhanced reliability. On comparison, the proposed concept outperforms conventional ones in terms of efficiency, ripple reduction and stability making it a better solution for improving PV system performance.
	Keywords: interleaved Boost-SEPIC Converter (IBSC), passivity-based control (PBC), photovoltaic (PV) systems, proportional-integral (PI) controller, pulse width modulation. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.15
16	Unified Power Flow Controller for PV Systems Using AI-Driven Power Quality Improvement Using Coupled Inductor Dual Boost Converter Authors: 1Chindam A., 1IlanjiAkilandam C., 2DugyalaV. 1Annamalai University, India 2Kamala Institute of Technology and Science, Telangana, India.
	Abstract: Voltage stability, power flow regulation, and Power Quality have become major issues as a result of the increasing integration of renewable energy sources, especially photovoltaic (PV) systems, into power transmission networks. The main objective of this research is to improve the power quality (PQ) in power system utilizing Renewable Energy Sources (RESs), notably by eliminating the harmonic content in voltage and current that arise from power electronics interfaces. To address this, a Unified Power Flow Controller (UPFC), is proposed comprising both series and shunt converters interlinked with DC-link capacitor. In addition, a Photovoltaic (PV) system is integrated with a Coupled Inductor Dual Boost (CIDB) converter to ensure a stable and continuous energy supply. To accomplish these objectives, a Coyote Optimized Radial Basis Function Neural Network (COA-RBFNN) based Maximum Power Point Tracking (MPPT) is adopted for ensuring efficient energy extraction from PV system. Furthermore, a Decoupled Neural Network (DNN) based control technique is integrated to manage UPFC efficiently. The research is modelled and simulated in Matlab. The most important results of the study demonstrate a significant improvement in improving PQ, even under changing load conditions. Moreover, the converter ranks with improved efficiency of 88%, with improved voltage and current characteristics. The significance of the results is found in the ability to integrate renewable energy with contemporary power control technologies while guaranteeing dependable and high-quality power delivery.
	Keywords: power quality (PQ), PV, Coupled Inductor Dual Boost converter, Coyote Optimized RBFNN MPPT, DNN. DOI: https://doi.org/10.52254/1857-0070.2025.3-67.16